I won't bother repeating the above but I will go on to explain why the 4770K runs so hot.
It doesn't run hot directly because of hyper threading, it runs hot because hyper threading is an intensive cpu action that consumes a lot of power. I just wanted to make it clear that heating issues are the fault of hyper threading, but the fault of power consumption caused by using such intensive actions.
As for overclocking issues, I'm not aware of any. You might be referring to what is common with all Haswell chips being that because of the voltage regulator, NONE of the Haswell chips can be overclocked very much. However, it is wrong to assume Haswell desn't perform better than Ivy bridge did.
Haswell performs better at lower voltages, making it defacto overclocked as compared to Ivy Bridge at like speeds (4.0GHz Haswell uses less power than 4.2GHz Ivy Bridge with same performance).