Aren't they Wii games? We're talking Gamecube here, the CPU is half the power.
Multithreading is perfectly possible in apps, and if it was well made it wouldn't need a massive clock speed...
Umad? I have N64, PS1 and Even GTA III (PS2) Emulators running flawlessly on my single core Xperia PLAY. Imagine how much better it would run on a Tegra 3 or 4?
Hell, there's even a PS1 emulator for the Dreamcast >.>