Clamp-on brake for undrilled forks?

Has anyone used one of these clamps for the rear?

I'd be using it to get myself and the bike to the track and don't want to clamp anything to the carbon forks, and I won't do 85" breakless.

http://www.sjscycles.co.uk/product.asp?pf_id=20984&src=froogle

i don't think anyone answered this, but maybe thats cos no one has the rear versions,

has anyone used the rear version, the plates held with one bolt don't seem as sturdy as the the front dule clamp job, but i reckon they might look less bulky/stuck on then the front versions

anyone got any thoughts?

second question, why would i have a brake hole at the wrong angle anyway? unless i've made some rookie mistake with that queston