Aray Ali bhai, you'll never understand Intel's strategy... It's an "expected" performance gain you're talking about, Intel is not fool to give 50% performance boost after every fucking year.
I've said it before, and I'm saying it again: Only launching pace has increased whereas the performance punch remains the same (i.e. 15-20%). Same performance gain we got in the Sandy Bridge as well after Lynnfield (3-years) and also same performance gain is "expected" in the LGA-1150 CPUs too.