I have completed my mission here. You don't have to thank me, I did it for all of us. 

This question has been addressed in every single iteration of the "why hasn't this been banned" discussion yet. It boils down to the fact that you build the sets, and you completely control everything that the imposter can do. This puts BH teambuilding into a unique position that isn't really commonly thought about in any other format, where you need to make sure that your own team is balanced enough to deal with the rest of your mons as imposters (imposter-proofing, or commonly improofing). At this point, imposter has been around for the entirety of the competitive BH metagame ever since Gen 5, and because of its trait at only doing what your mons can do, on top of the fact that you can easily prepare for its options because you yourself brought them into the battle, it is commonly seen as one of the largest balancing agents in BH.I truly could never find a good reason as to why imposter chansey has been banned. It is by far the most restrictive mon in the entire metagame and forces players to design pokemon for the sole person of taking it out. There has already been precedent that a single pokemon that force other teams to built around/for it are too restrictive on the meta game and should be banned. Many counters require some form of set up or have trouble finding any use other then just defeating imposter chansey, not to mention how a lot of imposter chansey teams are prepared to defeat your counters.
It has made the meta unhealthy and restrictive where even if you make the right plays you can still lose. I see no reason why it is not being suspect tested and banned already
My main issue here is that the amount of item choices that you have mentioned. Yes they exploitable but there is no way of telling until they have already played their cards, forcing me to guess not to mention how imposter, espeically imposter chansey or blissey to me is simply just too polarizing. The idea that the outcome of a match can come down to a speed tie constantly or I don't know if its scarf not is simply just not fun and it makes it more about luck. Of course it not impossible to defeat, I am rather high in the ladder myself but I simply just dislike how much of a stranglehold it has on the meta. In the post you sent, they also discuss sturdy shedninja, a mon that people also argued was healthy cause it has players plan more carefully when making teams, which was later banned for a similar reason. It was too restrictive and players were forced to guess which set it was running. Different shedninja sets had different weakenesses but you couldn't tell what set it was running until it was too late. Obviously imposter is not on the same level but I feel like arguing that its existence is a healthy part of team building because it has the player make very careful team choices is rather far fetched when so many others mons have been banned for a similar reason. We both clearly agree that its restrictive to some extent but it seem the disagreement comes from if its healthy or not for the meta.This question has been addressed in every single iteration of the "why hasn't this been banned" discussion yet. It boils down to the fact that you build the sets, and you completely control everything that the imposter can do. This puts BHteambuilding into a unique position that isn't really commonly thought about in any other format, where you need to make sure that your own team is balanced enough to deal with the rest of your mons as imposters (imposter-proofing, or commonly improofing). At this point, imposter has been around for the entirety of the competitive BH metagame ever since Gen 5, and because of its trait at only doing what your mons can do, on top of the fact that you can easily prepare for its options because you yourself brought them into the battle, it is commonly seen as one of the largest balancing agents in BH.
Flint (the old tier leader) posted about it in this post here with the same sentiment. Imposter is one of BH's largest constants, and players need to be aware of this nuance in teambuilding if they're expecting to build competitive and consistent teams. The thing to remember is, as much as BH is a sandbox meta, it is nowhere near unlimited, and there need to be checks on common brokens and building styles for the meta to be healthy.
edit: I forgot to add, Imposters are also extremely limited. They want to do too many jobs that their item slot and 5pp limitation doesn't allow them to do. They're extremely consistent, but they will almost always have exploitable flaws depending on their item choice. For example, eviolite gives them more bulk while sacrificing the ability to switch out without being trapped and always being at risk for speed ties. Choice scarf guarantees outspeeding the opponent, but they are locked into 1 move and more easily exploitable. Shed shell gives them the option to switch out no matter what at the cost of bulk and speed. Toxic Orb helps with their poison heal matchup, but hurts everywhere else. Pikachu and other non-chansey line imposters are frail as fuck. All imposters eat shit vs bellyburdens and other self improofs unless they're running extremely niche sets. The list goes on and on.
It seems you have completely missed the point. No one is complaining about unpredictability, the main issue here is that counters to imp sets can usually be defeated by just the same set but different items. things that should counter it can end being hurt by something as simple as an item change. The problem here is that its hard to prepare for every set and matches will sometimes be decided off of which set your opponent brought in rather then any sort skill. Plus you are only responding to one minor point when my main focus was discussing the restrictiveness and how its unhealthy for the meta, if you're going to ignore the rest of that then I see no reason to keep talking.It's an astoundingly weak point to complain about Imposter's unpredictability in items despite you controlling everything else when the rest of the meta has unpredictability in not just items, but the ability slot and move slot as well. If unpredictability is something you struggle with, BH isn't the meta for you. Your improofs should be able to answer imposter regardless of the item as well, that's what makes teams good against Imposter.
Well, sometimes they sorta can, but those are much rarer and mostly apply to self improofing, like a chill drive Chansey beating a normalize Calyrex or a toxic orb chansey beating PH mons, and it’s entirely predictable what sets can be beaten like this and this should have a backup check on the team for.They really can't be invalidated by a change in items. If your counter to something comes down to a speed tie, it's not really a counter at all.
First of all, to address one of the larger misconceptions in this post, shed was banned coming into the new gen because of the addition of new and extremely viable options that pushed it over the edge (namely boots and players learning how to absolutely exploit it to the best of its potential at the end of the gen, see cityscapes' 2k elo bounce spam + shed team, sugarhigh's shed + gambit spam, BMOC style gars + sheds, etc). In that aspect, that post is out of date because the meta and strategies revolving around shed completely flipped on their head. However, the meta and strategies revolving around imp have mostly stayed constant, aside from the change in usage percent of shed shell and scarf maybe instead of the overwhelming majority of imps being eviolite.My main issue here is that the amount of item choices that you have mentioned. Yes they exploitable but there is no way of telling until they have already played their cards, forcing me to guess not to mention how imposter, espeically imposter chansey or blissey to me is simply just too polarizing. The idea that the outcome of a match can come down to a speed tie constantly or I don't know if its scarf not is simply just not fun and it makes it more about luck. Of course it not impossible to defeat, I am rather high in the ladder myself but I simply just dislike how much of a stranglehold it has on the meta. In the post you sent, they also discuss sturdy shedninja, a mon that people also argued was healthy cause it has players plan more carefully when making teams, which was later banned for a similar reason. It was too restrictive and players were forced to guess which set it was running. Different shedninja sets had different weakenesses but you couldn't tell what set it was running until it was too late. Obviously imposter is not on the same level but I feel like arguing that its existence is a healthy part of team building because it has the player make very careful team choices is rather far fetched when so many others mons have been banned for a similar reason. We both clearly agree that its restrictive to some extent but it seem the disagreement comes from if its healthy or not for the meta.
I quite dislike Volk's wording here, but his sentiment is right. I feel like you (tacocat) are arguing about a much smaller point that is just a side effect of having imposter in the meta while ignoring the fact that the format would look completely different and be even more unpredictable and inconsistent without it.It's an astoundingly weak point to complain about Imposter's unpredictability in items despite you controlling everything else when the rest of the meta has unpredictability in not just items, but the ability slot and move slot as well. If unpredictability is something you struggle with, BH isn't the meta for you. Your improofs should be able to answer imposter regardless of the item as well, that's what makes teams good against Imposter.
I think you missed Volk's point here. By removing imposter, you are removing any semblance of predictability in the format, and that is a much larger issue than someone's team struggling vs imposter because they don't know how to prep for it. At the end of the day, I can't really think of any item choice that Imposter can run that can cause it to overcome every single one of its flaws. Period. There is ALWAYS a drawback to its item, and if the item isn't the drawback, then they only have 20 turns max of PP to use before they need to switch out and try again.It seems you have completely missed the point. No one is complaining about unpredictability, the main issue here is that counters to imp sets can usually be defeated by just the same set but different items. things that should counter it can end being hurt by something as simple as an item change. The problem here is that its hard to prepare for every set and matches will sometimes be decided off of which set your opponent brought in rather then any sort skill. Plus you are only responding to one minor point when my main focus was discussing the restrictiveness and how its unhealthy for the meta, if you're going to ignore the rest of that then I see no reason to keep talking.
pretty much this. The item is the only thing that really changes Imp's strategy, and there are much more consistent ways to improof something than going for a speed tie. I'd suggest you try and look into self-improofing sets with moves like Techno Blast or Anchor Shot.They really can't be invalidated by a change in items. If your counter to something comes down to a speed tie, it's not really a counter at all.
Sets like these lack consistency in the first place and fall flat on their faces when trying to be viable in the widespread format, missing out on concrete benefits that are always active like scarf, eviolite, or shell. They can be used (we both know this) but are you really going to bring these when you can bring something infinitely more consistent?Well, sometimes they sorta can, but those are much rarer and mostly apply to self improofing, like a chill drive Chansey beating a normalize Calyrex or a toxic orb chansey beating PH mons, and it’s entirely predictable what sets can be beaten like this and this should have a backup check on the team for.