A question of etiquette

WARNING:  Adult content.  Do not read further if you do not want to encounter adult content.


In conversation yesterday, Kyle raised a question of etiquette that none of the etiquette books I've read (yes, I have read a few) ever addressed:  

"When you're getting a massage, and the masseuse is rubbing the inside of your thighs, what is the right amount of chub to show?"

To clarify, Kyle was referring to a normal massage, not one in a trailer with "Happy endings $100" and "All girl staff" signs on it.

Kyle was leaning toward a middling amount, on the theory that showing none would be insulting to the masseuse but that going full tent-pole would be intimidating.

When I asked a few women, all of whom declined to let me name them here, for their opinions, I found no consistent answer.  Responses included

"None; if you want that kind of massage, go somewhere else."

"None; ask them to turn up the air conditioning."

"Enough to show interest but no more." 

What's your answer to this unexplored matter of etiquette?