Difference in Technical? -- NCAA vs. NFHS

[hawkk]

I'm playing D in the post:
I MAY wave my hand in the passing lane to distract the passer and the receiver of the ball.
I MAY NOT play defense by staying behind the offensive post player and wrapping my arm around his head and holding my hand in front of his eyes so that he can't see the ball.

You don't see it called b/c players don't do it.