Attack=15: the only relevant IV?
To optimize my teams, I've been studying breakpoint spreadsheets recently ... it's astonishing how little difference the defense IV (and even level, within reason) makes in how much damage is taken. But for attacking, it's a completely different story, and the damage scales predictably upward with increasing level AND attack IV.
Granted, this is with favorable counters, typically dealing SE damage and taking NVE, but this should be how we all battle bosses (at least for GP readers!), so it's real life IMO. Adding in the ability to dodge at least charge attacks makes the defense IV even less relevant.
TL;DR - feel good about evolving and maybe powering those wild catch L30 with best attack stat even if overall appraisal is otherwise only average (or worse?).
Answers
Both are relevant.
It will depend on the mon (and it's base stats) as to how much either def IV or att IV will make.
Everyone seems to be on this bandwagon of 'my dps break point' boosting...where as your defence will have an effect on your opponents 'dps break point'.
Def IV is the other side of the same coin - to say it is irrelevant basically also says that attack IV breakpoints are irrelevant.
I get your point about dodging...but that has become far less relevant with the recent changes to gyms, and in raids - except for a few specific situatiuons.
TBH...I was hoping to see spreadsheets that show us at what point our defence will influence the quick move break point of Mewtwo.
That is, if I could get a reduction in damage to me done by Mewtwo's quick move(s) with a small power up, then it would be just as beneficial to power it up again.
Basically...without the defensive breakpoints listed, then the spreadsheets you refer to are only telling you part of the story.
This is that part where I beg plead and grovel for the GP overlords to make a calculator that can do every mon now and in the future, for def and attack, for fast and charge moves...but I am starting to get sick of asking, so I won't bother.
Def IV is the other side of the same coin - to say it is irrelevant basically also says that attack IV breakpoints are irrelevant.
Defenders attacks so much slower than it do not matter that much.
Especially tier 4-5 bosses get so much energy from CP loss that they have full energy bar almost all the time, and most damage you get from boss comes from his charge moves, and for charge moves breakpoints are not that critical.
Son, you are lost in the stats and numbers.
Sure, the Atk IV is the dominant factor ok. The Def and the Sta IV determine how long you will be there attacking. Simple as that. Atk has 2X weighing factor in the CP number. That's already been recognized by Niantic.
Say a high IV mon will last 20 hits, say a low IV mon of the same will last 19 hits. You argue that 1 hit matters not, but in surprising number of battles, it will.
That's the diff.