Chansey is consistently hovering around the OU/UU border, so it does matter. Jirachi still stands because of Dragonite's pathetic speed. Latias lives due to Leftovers. I might've made a mistake with the Rotom-W calcs.
However, you assume that you predict right every time. There are many pokemon who can come in on one of those moves and proceed to KO. For example, what happens if you try thundering an opponent`s Skarmory and Latios comes in? Because of Life Orb, you are no longer under the protection of Multi Scale and you're gonna die. Also, for a wallbreaker to be considered successful, it must be able to either make multiple KOs, or score a KO and put nasty dents into 2/3 other pokemon. If MixMence manages to take out 50% Infernape, then dies immediately after, this is not a mission accomplished. I've played with and against Rain MixNite of all sorts, and it was underwhelming on both sides. I found I could never score more than one KO with it, and when I played against it, I found it would never take more than one poke with it, and thats usually some random Celebi at 20% it takes out as well.
For the Life Orb variant of Dragonite, I say, why bother? Just use the Outrage, Draco Meteor, Earthquake, Fire Blast Salamence. Screw 2HKOs, that thing OHKOs like 3/4 of the metagame. Even Balloon Heatran isn't going to enjoy Outrage at all.
First of all Chansey is not hovering anywhere.
She is solidly UU.It was number 60 in OU usage and number 10 in UU usage this August.
You can still use her sure but she is a rare sight and since she is out of ou let's leave her out since i asked you for OU pokes that don't get destroyed by Dnite.
Prediction is required with all wallbreakers my friend and even more with Mixmence.If you get too cocky and spam DM at the wrong time(When a steel type comes in)you now have no special attacking presence.
So i don't really see why this is an argument against Mixnite and not wallbreakers in general.
Also about the part which a wallbreaker must kill and damage more than one of the opposing memebers to be succesful i have to say this.Most opponents who see a wallbreaker will try to overpredict him so they can safely bring in something that can kill it(either outspeeding it or with priority).So when they switch in a poke that can get 2hkoed by the wallbreaker they don't just let it die,usually,they just switch out trying to get a safe switch.
That's why these pokes are called wallbreakers.They soften or kill the opposing walls so that your main sweeper can get a clean sweep.
Do you get it?
So as long as Dnite can 2hko almost any wall in OU you are free to sweep with your sweeper when that wall is removed or heavily injured!
Games are not so simple as you make them be.It doesn't go like:''i have a poke and if it kills one we are even''.
Also after Dnite kills something the next poke is going to take a big hit if it is slower or a a strong priority hit if it is faster,except for a few things like faster steels,ghosts and terakion(they take little from ES and they outspeed Mixnite).
Also about the part where you used Mixnite and you were let down the reason was simple!You were using it poorly.In my rain team it is an mvp many times and softens walls very nicely before something like Thundurus sweeps.
And finally about your point on Salamence.I have mentioned again the reasons to use Mixnite over Mixmence.
These reasons are:
A spammable strong special attack that doesn't lower your S.atc.
Higher bulk.
Priority.
Different coverage and thus different targets get hit better from Dnite.
Element of surprise.
Now the reasons to use Mixmence:
Higher speed.
Stronger special attacks right of the bat.
Different coverage and thus different targets get hit better from Salamence.
The potential of having Roost,due to having already excelent coverage with 3 moves.
For me both are superb wallbreakers that work very good.For you the one is good while the other isan't.That's fine but please stop spreading the misconception that Mixmence outclasses Mixnite as a wallbreaker and that rain abusing Dnite sucks.
