or are you saying you know something more than the fine folks at apple?
No, I'm responding to the OP that asked about the origin of the stutter some people have complained about.
Your screenshot says
nothing about what Apple think "may" affect performance, and an objective analysis of the hardware makes it clear
it is not hardware based. Therefore this is a software issue; unless you have evidence to the contrary?
Will Apple optimise their drivers and WindowServer drawing code? I suspect things will get better, though I personally have little faith in the GPU driver engineers at Apple. Luckily, at least for me, the rMBP works wonderfully in the real world under heavy workloads even at the "may affect performance" 1200p, today.
The only reliably reproducible unusable UI performance I can elicit is resizing the App Store (quartz debug shows a glitchy ~10fps), but that even floors my 2012 ATI5870 24GB octocore Mac Pro running a 2560x1440 non-retina Cinema Display (also ~10fps), so this is not rMBP specific. The fact some people see this depending on the
browser they use, or in the case of the Spaces animation depending on
what program is running in the destination space or what
settings are applied to the dock just confirms this is software based.