I agree with your criticism of design dogma - it drives me nuts too - people saying something bad is good because it follows the rules. But since I'm also responsible for the Android icon shape-change you talked about, let me waffle for a bit in case it helps provide a perspective on the other side of that decision:

I agree with that the non-uniform icons are easier to find, and that uniform shapes make it harder (I also agree that uniform colors are awful, but that was after my time so I have no stake in that).

However, usability is not about pure efficiency - a huge amount of it is approachability - people have to _want_ to use the UI. If they don't want to use it, no amount of pure-usability work will mean anything - it will just be "shitty computers" in their heads. In Android's case, the developer-provided weirdly shaped icons were a major sticking point - people would take one look at an Android homescreen with all kinds of mismatched splatters of icons, mentally lump it with Windows and Linux in the must-be-for-geeks bucket, and walk off to the Apple store.

It drove us nuts - in actual tests, people would often find Android easier and more efficient to use, but would still pick iPhone as the "easier" product, because that's the one that was inviting, that fit their style, that looked easy to use.

So we did a lot of work nudging Android to a place where real people would find it desirable, easy, and powerful - making really difficult tradeoffs - sometimes breaking expectations, sometimes sacrificing a little bit here and there to gain a lot somewhere else, sometimes just taking a chance.

It took a lot of effort from a lot of wonderful people, and it involved a stupidly large amount of arguing against "just copy iPhone" laziness and pressure (a major reason I left), but I am still deeply proud of what the team was able to do. We couldn't please everyone, but I think more people were pleased afterwards than before.