Trained hundreds on the Glock. Missing high isn’t in the top five challenges shooters face.
Grip angle and trigger are subjective concerns which lead to bias. I’ve laid out the objective reasons.
We have pretty objective methods for comparing triggers. To say it is subjective is simply inaccurate. And we have a whole lot of biology and kenesiology to tell us what the most natural grip angle is. There's a reason almost everyone but Glock uses the more natural angle.
If you haven't had students missing high, that's good. That's probably because they had a good teacher and he laid out the basics of a good grip before they got into bad habits. And he tweaked their grip problems along the way. But I can tell you by the time a friend tells me of their problems, bad habits have already formed. And with Glocks, that often includes shooting high. More so than you would see from any other pistol in the hands of a novice. I can about guarantee you that 90% of Army pistol shooters will not receive quality training. I never did for my secondary when I was an M240 gunner. There are still bad rifle fundamentals being taught in some basic training rotations, for that matter.
And I have laid out objective reasons which I feel would have meant more to the Army. But your bias is weighted toward certain objective factors. There's a whole bunch of reasons to go with any number of the pistols that were at the trials. But there will only be certain ones that carry enough weight to win the contract. The ability of a soldier to break his own weapon down past a field strip, for instance, is not even on the Army's radar. In fact, the thought of Snuffy out there in the woods with his pistol in more than 4 or 5 pieces is probably downright frightening to Army brass. And I wouldn't blame them. Is that a great reason to go with Glock? Absolutely. But not to the Army.
Objectivity is only objective so long as the objective material is not subjectively selected. And we will all apply our own bias. All I am trying to point out is that this "should have gone with Glock" nonsense is ignorant of the entire selection process, and leads to attempts to impose our own values on the decision making process of an organization that is nothing like a private citizen or even an LE agency. Many people choose Glocks because of the unparalleled aftermarket support they have. But the Army doesn't care about that, they make their own aftermarket support. How many LE agencies require a manual safety? Not a lot. But I can't imagine a world with Army small arms that were not equipped with safeties.