it's a thug life ¨̮
That's my entire point, I do not think Surf is a reasonable substitute in a tier where each typing has its own bag of tricks.Perhaps Robert hasn't backed up the point in the first part of his post too well, but I think his second paragraph makes a lot of sense. What he says is that it's all good talking in theory about how moves like Body Slam, Lava Plume and Thunder are similar to Scald, but in practice Scald is a lot more worthy of a ban because it has a much more of a concrete impact on the metagame.
Scald is always going to be in the backs of a player's mind when building a team because nearly every single Water-type Pokemon is going to carry that move. There is only one Pokemon in OU (both BW and ORAS) that uses Lava Plume effectively, and that is Heatran. Furthermore, Scald hits the only type immune to it super effectively. The same can't be said of Lava Plume. Finch summed it up really well on the previous page - "It gets less distribution among Fire-types, is often not used in favour of alternatives (like Fire Blast), and doesn't have the same niche as a Water-type move inflicting a burn". It's really no comparison; Scald has way more of an impact on the metagame than Lava Plume does. Regarding Body Slam, there is also only one Pokemon in OU that commonly uses it, and that is Jirachi. Body Slam also has terrible coverage and power, and so has pretty much no use outside of the 30% chance of paralysis. Scald has excellent distribution, decent power boosted by STAB, and can even be boosted by Rain. Not much comparison here either.
Lava Plume and Body Slam are not a big deal not because of immunities or how many Fire-types there are, but it's simply because there are 2 Pokemon in the whole of BW and ORAS OU that commonly carry those moves. Even if you look at ORAS UU, the only Pokemon that uses Body Slam is Snorlax, and there are absolutely none that use Lava Plume. Scald is used by nearly every single Water-type out there. Even not keeping in mind the other factors I mentioned, isn't it reasonable to say that it has a far bigger impact than the other two moves simply because of its sheer usage? And once you consider the points that do make Scald superior, you can see why it's considered more ban-worthy than other similar moves.
Also, I think people are vastly overrating how easily Scald is to take in practice, even by Natural Cure and Heal Bell users. If Pokemon having such abilities and moves get burned by Scald, they are still put under significant pressure. The likes of Celebi and Starmie can be weakened to the point that the burn could potentially put them in range of a KO, or it could force them to Recover which results in a loss of momentum. For Heal Bell users too, Pokemon like Chansey and Blissey are so passive offensively as it is, and taking up a turn to use Heal Bell can again prove quite detrimental in terms of momentum. As for Water Absorb users, there are none that are actually in the OU tier in ORAS which says a lot about their usage.
Really, it just comes down to how crippling people assess Scald and its secondary effect to be in the tier in question. Looking at posts from other tiers, RU and NU players don't really feel it's broken at all. However in UU, and maybe in ORAS and BW OU as well, Scald is surely significant enough to be controversial. radiant also brought up a good point in that banning Scald would not make most bulky Water-types any less viable due to their access to Surf. It isn't much of an argument for banning Scald in itself, but it's definitely something to keep in mind if any tiering action is going to be considered.