Originally Posted by FBinNY

You're assigning too much meaning to the clothing.

People may wear that stuff for practical reasons, ie the helmet for protection, the shorts and jersey for comfort, and the shoes and gloves simply because they prefer to. That doesn't mean they have any illusions about being part of the road culture you seem to believe exists.

Then there may be a retired racer who dresses that way because he always did, and doesn't have a reason to stop. Or an active racer out training, who simply prefers not to be drafted by unknowns, outside of the sanctioned, licensed race environment. He might even be a cat 3 or 4, who doesn't some cat 1 poseur (as you might describe him) on his ass. Or he might be OK with drafting, but consider that particular stretch or road as unsuited for close riding.

So, kit is a meaningless basis to assume one would or should be OK with you latching onto his rear. The simple rule, based on common courtesy, is to assume nothing at all, and not to draft strangers outside of conditions where it's clearly OK, ie. a race.

of course, you can always pull alongside, introduce yourself and ask if that person wants to alternate drafts with you.