Is IV still relevant for Blissey?!

From the information we have so far, it seems like cp is MUCH less relevant than before and therefore IV's are also much less relevant. For attackers level is more important than cp and movesets are FAR more important (even moreso than before, but at least now we have TM's) and for defenders it's rather unclear, but surely a few cp points won't make anywhere near the difference that it used to.

Whereas powering up high IV defenders was one of the most crucial parts of PoGo before, now we MIGHT have a situation where you can spend your stardust more leisurely on pet projects and a wide range of attackers.

So yeah, in your example, I would probably evolve the high level Chansey. Not so much for the stardust saving, but Chansey candy are really hard to come by.

One caveat though, is that besides all of this still being somewhat speculative, another thing we don't know is if IV's will become important again sometime in the future. With TM's introduced, IV's are the only thing about a mon that you cannot improve over time, so that is one argument for still paying some attention to IV's.

EDIT: I will add that I totally regret maxing out my two Blissey just recently. A third Blissey would have been much more valuable to me. I think now more than ever, you rarely want to power up beyond level 30 unless it is something like a Vaporeon, where candy is fairly easily obtainable.

We have no idea.

One thing people are missing is this...
Doesn't it make sense that a high IV Pokémon, that the appraisal says things like "will be amazing in battle" would ACTUALLY be better in battle than a low IV one?

What I'm saying is...it really makes sense for them to make IV more important than just to boost CP. Therefore, maybe some day (maybe now, we don't know) it will

IV will still influence when the break points for damage done/taken because of flooring.
Blissey needs most help witrh 'attack anyway...and that happens to be what gives her the biggest CP increase.
Indirectly, IV still matter.

...but we are talking fractions here.

Blissey's stats are
129 attack
229 defense
510 stamina

The way ivs work is that (I believe this is correct) the number a Pokémon has (e.g. 14/10/13 for example) will be the base stats plus ivs. So I'm blissey's case, it has nearly half attack as it does defense and nearly a quarter attack as it does stamina. Therefore, proportionally, blissey benefits from attack ivs, as it already has solid defense and HP. If you have options for chansey's, I'd go with the ones with the highest attack stats

As far as defense and hp, they don't matter nearly as much, as cp is no longer a determining factor for
Gym placement, and she already has huge defense and hp stats

The only reason to believe IVs will make a comeback is that they are probably far more profitable for Niantic if people need to use incubators to get higher IV mons...This was very important in stagnant competitive gym areas.

Even with the damage floor, without a general need for higher IV mons, incubator sales would probably decrease since getting slightly more CP isn't going to help much.

People talk about stardust, but you can now soon feed any gym defender to get 50 stardust per berry it seems...

TL:DR: A lack of importance in CP will nerf Niantic's sales of incubators IMO...which may eventually see a change in IV's importance again in the future...

From my point of view nothing changes. The highest IV the better. A high IV pokemon will always perform better in battle. Since space is limited either in gyms and in our storage I will keep collecting the best IV possible only. That strategy is supported by the introduction of TMs.