[Andy W]

are boulder grades based on onsight or worked, just a thought? or something inbetween?

[r-man]

Bouldering grades refer to the easiest method of climbing the problem.

So they are for a worked ascent, not an onsight.

[fatboySlimfast]

Deja vu of a bloody rocktalk discussion here....................... :roll:

[r-man]

What's to discuss?  :?

[Falling Down]

Your third option was correct.  Boulder problems are graded based on just a thought... thoughts that the first and subsequent ascentionists had when considering the difficulty of the problem he or she had just climbed relative to others they had previously tried or failed upon.