Hi John,
I've never been a huge fan of the smelly stuff. I didn't think the risk of spilling it on my carpet warrented any difference made in fish catching of the lure it was on.

That said, this spring, I began using crawfish scented smelly jelly (nasty stuff) on some of my lures and found the lures with it on were out fishing "naked" lures by 2-1. This was totally unscientific as the lures were perhaps at different depths and different speeds (inside vs outside of turns). It was enough of noticable difference though that guys we shared our rental with began using it. I definitely don't think it hurts...just don't spill any.