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A) writing a script makes it so you only have to do it once, umm thats the whole point

B) If you don't understand why mergemaster is not needed for a simple patch, do some reading its quite...

Have you ever heard of writing a script? ie
cvsup -g -L 1 /root/sourcesup;
cd /usr/src;
make buildworld && make buildkernel KERNCONF=blah && make install K......

mergemaster is not needed...