Maybe they were coachable moments, but let me show it to you from the other side of the line:
Player does exactly what I taught him to do. You, the less experienced official (and I'm speaking hypothetically, not you IA-HL) call it it foul, when I know that you simply don't understand the rule, and that any good varsity official isn't going to call it that way. I want the player NOT to be discouraged by your flag, I want him to know he did exactly what I wanted him to do. I may well encourage his behavior despite your call.
I'm NOT trying to justify every i-di-ot sub varsity coach out there, and there are certainly plenty of them. But I'm not going to defend every "less experienced" (or incompetent) sub varsity official either, are there are plenty of those as well.
And I assume by putting the USC in quotes, you realize that someone on our crew is fitting into the "less experienced" crowd here by calling that a USC instead of a DBPF. I wasn't there, I'm not saying it wasn't a foul, but if it was as you described, it sure wasn't a USC either!