All though I partially agree with Semidevil, I'd say run your own tests. Do a P4 system both ways and run some benchmarks (i.e. Sysoft, 3D Mark, etc.) and prove to them what is better.
It should be easier to find the thermal coefficients of different thermal materials and prove to them that the pink crap is BAD! If they keep putting large amounts of paste on stuff, then they obviously can't read the instructions that come with most paste. It could also seem worse than it really is if they're leaving the pink stuff on because it will squeeze more of the paste out then if they'd scraped it off first.
Just my mad rambelings.
