Objective: Create a fixed position header and footer while maintain the scrolling functionality cross-browser.
Looking at tables for position:fixed support you can notice, the support is fairly good these days. Still I meet people with Android running version Android < v3 and (maybe fewer) iPhones running version of iOS <5.
Point of having a website, not an app is to be accessible as much as possible. But what if you still want to have cutting edge design, even just to wow your customers.