Th NoClick function works by stopping the heads cycling between cyliners 0 and 1 to detect the change. Instead, the heads are constantly pushed to 0 (or -1, I can't remember). Most drives recognise this as an illegal head move and don't move the heads, but some will try to carry out the move blindly, forcing the heads against the stop at the end of its track. This can damage those drives over time, so you shouldn't use it.
