Empira, it all depends on the size of one's endowment.  For someone who is average or below-average, a padded dancebelt can be an enhancement under ordinary circumstances, yet have a camouflaging effect when necessary.  For a male who is above-average, the enhancement in the apparent size of non-erect penis can make it embarassingly conspicuous (alas, I don't have that particular "problem").  And an erection - he might as well have a signpost.  Believe me, no one is going to concentrate on his technique in class or performance at such a time.