Holding any clutch in, wet or dry, single or mulit plate isn't doing it any good but I'd doubt you'll burn the plates on tickover no matter what you did with the clutch lever.

Whether it's doing any real damage is another matter, if it's truely clear and most dry clutchs are, hence they rattle it's not doing much but the plates are still rattling and spinning against the friction material, both wearing and getting hotter and hotter.

Shockingly Tex (Alan Armour's mechanic) reckons the VJ23's are really sensitive to this and once the plates are hot and expanded the clutch doesn't clear enough to hold the bike stationary and in gear which might get a tad annoying on the startline.

You also see this sometimes in BSB/WSB when they hold them on the grid for ages and someone creeps forwards, they haven't let the clutch out, it's just got that hot its started dragging.
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