There was a previous post with the actual picture of a worn-out 6th gear syncro, the cause being 1->2->3->6 shifts...

 

Not sure if it's the most recommended method, but I skip shift only thing is when I know I'm jumping up a extra gear or two I never do this out of wide open throttle and I make sure and give it a second in neutral. Never had a problem with this method.

Kinda funny though i remember my Z28 required you to skip shift unless you were WOT.