NCAA Rule 6-6 wrote:f. Delaying the game—When for a team delay, the penalty shall be assigned to the in-home. Delaying the game shall be the consuming of more than 20 seconds:
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(6) For adjusting of equipment, 20 seconds to begin when the adjusting of equipment begins.
I always thought this was a bit vague. Can they get 20 seconds any time they want it? I wouldn't allow it, but the rules don't really say.
I will say that if the same guy needed to tie his shoes twice in the same game, I'd make it very clear that he'd better use a double knot, because the next time he tried it I'd be calling delay of game and it would be a turnover or 30 seconds. Similarly, if a team seemed to be using it as a tactic, I'd call a foul as well.
BTW, you can not get a horn if play is suspended for equipment issues; the rules used to say you couldn't have special substitution in this situation, but they've removed that clause (which is good, because I never thought it made any sense).