Isn't dazzling oncoming traffic is about beam pattern and headlight alignment rather than a bit of extra light output?
Partly, but think about it - if your normal beam pattern allows a certain brightness into the opposing lane (as it must for you to be able to see them, or rather them be able to see you) then having bulbs that are 50% brighter means what they see is 50% brighter too. Which can be just as noticable as your extra vision from them. I used to have 100/130W lights in my old car but so many people flashed me when they were in normal-beam that I got tired of searing their retinas with a return of my full beam (all correctly aligned)!
It's all a can of worms really. HIDs put out a lot more light than even uprated halogens, but proper projectors give such a sharp cut-off, that dazzling - theoretically anyway - is less of an issue than with halogens in reflector-type headlights. Ultimately it's a kind of 'yes, but...' isn't it?
Anyway, for me at least, driving a Corrado - which is quite a low thing, so quite prone to being dazzled - the main issues are eejits using aftermarket HID kits in reflector headlights, badly adjusted lights and 4x4s with headlights that seem to be level with my head. Next to those, a little extra glare from a properly adjusted headlight with a 50%+ halogen bulb seems neither here or there.
I used to run 110/100s in my Mk2 GTI with an uprated wiring loom and very rarely got flashed despite there being a lot of light on the road in front.