Let's not discuss about whose fault it was or whatnot. This is meant to be a 'System Idle Process' discussion. Lets stay on topic.
ok, here are a few facts about 'discussions about system idle process' :
a)It is not actually a physical process and probably it shows the CPU % UNUSED rather than actually eating up the resources.
b) Although it is not itself an actual process, it is responsible for triggering other heavily resource hogging processes like schedulers, auto defrager, indexing system and many more that i am quite not aware of.
c) Most people agree to the fact that system idle process is harmless and causes no resource hogging or whatsoever but thats because the problem occurs very very rarely and those people just happened to be lucky not to be affected.
For me, it usually sorts itself out IF i restart the PC. I think the process should stop whatever its doing when you start using some proggs, but for some reasons(prolly glitch or sthg?), it doesnt. that is what i think is going on when ppl get this problem.