SMC issues on a MacBook Pro Thunderbolt
normally the SMC (system management controller) should not have to be reset at all. However it is sometimes necessary when troubleshooting so when people say "last resort" that, they are simply saying is an uncommon problem. The SMC controls things like the fan in your mac and power flow (the reason macs are so much quieter than most computers). If this is not working properly and needs to be reset is is probably because of a hardware issue. Reseting it also does not hurt your computer. It simply turns the controller off and then turns it back on without affecting your hard drive, memory, etc. Finally if the problem does continuously reoccur you should go into customer service because it is probably a hardware problem and it is best to let them look at it.