Therefore a system make with 3, 3W Luxeons could potentially produce 240 lumens! This, of course if its propoerly built with proper voltage and regulated.
According to this:
http://nordicgroup.us/s78/#Watts%20Versus%20Lumens
A 10W MR16 is putting out 400 lumens, quite a bit more if you overvolt it a bit.
My HID would appear to be putting out about 600 Lumens, and that is about what I would consider minimally acceptable for fast night rides.