It seems to me like there are 2 different versions of "Glock grip angle" being discussed here. One (the left bias thing) actually has more to do with hand size, finger length, and trigger interface. The other is the actual angle of the grip and whether the gun "points high" or not for the shooter.
I probably don't have as many training badges or rounds fired as @TCinVA , but I do have more than a few thousand rounds through Glocks and other pistols as well. Also, regarding some of the performance metric qualifiers he mentioned:
Rangemaster Bullseye, 297, 298, or 299/300 depending upon who you ask, with a stock G45:
25yd 3x5 Freestyle, stock G19:
25yd B8 Freestyle, stock G45:
3:00 IWB concealed FAST w/G45. Multiple runs including a 4.94 clean. Note the lack of left bias even running at speed:
Now, to address part one of the question: Left Bias. I do have my rear sights drifted slightly right of center. I'd be more inclined to buy that it was something off in my trigger press were it not for the fact that whether it's 7yds or 25yds, fast or slow, I'm still getting center hits. Furthermore, even in shooting WHO I still get the same POI. If it was my right trigger finger pushing shots left, it should reverse in shooting WHO, right? The fact that with the same sight alignment, and same POA, I'm getting the same POI, seems to kill this theory.
Now, on part about "pointing high" I have come to agree with that 100%. When I switched to Beretta only for a month (2,500 rounds) earlier this year, I initially found the Beretta to point low for me. That's carryover from index from years of shooting Glocks. Conversely, when I put the Beretta down and picked the Glock back up, guess what???? The Glock pointed high! Amazing! So yes, a Glock points high for me...so what? Shoot the sights. You'll still hit what you need to. And also, within 200 rounds, my index shifted so that the Glock again presented correctly working at speed out of the holster.