Cycle accuracy is important, if your emulator is not cycle accurate the devs will have to manually add code to their emulator for games who have problems being emulated.Yeah i know many factors play into getting perfect cycles but hey we can still get playable framerates, on lower end systems even with these factors, you wont even see these discrepancies 99% of the time if you are at accurate speeds, you only have to be truly ANAL to care about perfect cycles
Take DK64 for example, it's a real mess on emulator and some golden bananas are simply impossible to collect without using gameshark codes. Another example would be Speedy Gonzalez on the SNES which just crashes when activating switches on anything other than Higan.