It can, especially when cleaning and lapping are done, also. Plus, any work on the nozzles has the potential to disrupt the spray pattern, which is probably of greater concern than a minor change is pop pressure. It doesn't take much to turn a "sprayer" into a "streamer."

In my experience, the affects of disassembly are rather unpredictable from one injector to the next. Reinstalling them without testing is a total crap shoot. You can get away with it some of the time, but not all the time.