Intel likely made the TDP 95W to improve yield... you shouldn't think of it as a 'chip meant for desktop'.You're comparing a 95w chip made for the desktop (Sandy) to a 65w Mobile-first Chip (Broadwell). ANd broadwell still keeps up. Imagine if it was designed for the desktop and given 30 more watts?
That's why Skylake, a full 95w chip meant for the desktop, is going to be a great upgrade for Sandy owners.
I still wonder about the 6600K. It might be the worst of the lot.