I have been trying to rebuild XFree86 RPMS using the CVS updates and because of some typos in x files and the spec I had to do it number of times (it takes many hours to compile)...I could slowlt solve my problems throught -bc and -bi with --short-circuit so that I did not recompile from scratch each time....but at the end I saw that there was no option to so the final binary files without restarting all over again although the -bi stage was all done.....
No. The idea behind RPM is *reproducible* builds; hence, anything that builds actual packages has to go through a full run of the spec file.