Thanks for the link druuna
I used to run a system called Sourcemage which was able to (re)compile all applications whenever required.
My normal time to do this would be either a new version of glibc or a new version of gcc at which time I like to refresh both and their dependencies.
So from that point of view I am agreeing with only recompile (and doing a full rebuild) when improvements come along.
My current system is still relatively fresh and I am ironing out little problems and trying to improve my packaging system.
This is where I was wondering if my current choices of settings, basically those from the final build of glibc minus the /tools options, need to be altered
to basically say "use what the system has to rebuild".