I have a latest-model rMBP 15" with a R9 M370X. I use it for developing iOS apps and it works great… even with long periods of repeated tweak+compile sessions,

I have a latest-model rMBP 15" with a R9 M370X. I use it for developing iOS apps and it works great… even with long periods of repeated tweak+compile sessions, it only gets moderately warm and still manages good battery life. The only thing I can find that really gets it cooking is WoW, but laptops aren't made for gaming anyway and the heat is fixed by dropping WoW's settings down to something more reasonable. The thing about modern Macs is that Apple designs the hardware (and OS, for that matter) assuming that the user will be running well-written, efficient applications. When you use software like Chrome and Hangouts where efficiency wasn't ever a serious consideration and extended periods of 100% CPU usage are a given, well yeah, of course you're going to get a lot of heat. The solution is to use (and thus, encourage the creation of) well-optimized, efficient software, not to cram in more cooling. Honestly, there's no reason for desktop software to be as gluttonous as it is. If desktop software developers went to the lengths that mobile devs do to make things runs smoothly, we'd be in good shape. It's fine to make use of the absurd power than modern computers afford us, but only do so when the power is truly needed (video encoding, etc) or when there's some significant benefit to the user. Even then, do so in an intelligent way (use CPU cycles for the actual task at hand, not for expensive abstraction layers, VMs, etc) and offload as much as possible to HW acceleration instead of lazily dumping everything on the CPU.