Power steering assist fails while slowing down and turning

Hey everyone! So, I have been digging around multiple message boards and apparently this is a common problem that at some point, GM declared that it was just "Normal vehicle behavior".

I would describe it as follows: I am driving along just fine, and everything is running well. I hit the brakes to start slowing down to either hit a roundabout or turn into a driveway (always turning right), and the power steering assist seems to fail, and the wheel becomes very difficult to turn for 1-3 seconds, then the assist kicks back in, and everything is good again.

It is doing this more and more often and I haven't found any clear paths to fix it or reason why it would be doing it. The mechanics report that the power steering fluid looks clean, and the levels are good. And that the pump doesn't appear to be failing (maybe because they can't duplicate the problem).

Any ideas? PS fluid flush and add conditioner? Seen this before? Thank you!