I can not find it (or something similar) for eos 400D.
Also i will not use the function if it was available.
Yes, indeed.This is confusing. So it's basically the same as Tv mode in manual mode? How silly!
Shutter and aperture isn't that fixed as i thougth for two years.
I don't know if AEB in M-mode is an intentional function or a co-incidental side-effect (? ) ( i like to provide you with some selfmade English)