I don't know for sure, but my guess would bethis:

At Idle gas is moving trhough slowly, so the gel wouldn't neccessarily be drawn up into the carb itself in large qty.

If you ride it, working the throttle you draw larger amounts, quicker through the carb which could suck big chunks of gel at one time.

That's my guess anyway!

I didn't know about the gel until after I'd done mine, and didn't see any really adverse affects. I rode mine and got pretty wild with it right away. I did notice some minor surging, etc. but nothing major. I also added a double-trength dose of gumout carb cleaner to the first tank to help get rid of any varnish that might have built up since they test started them at the factory.