The argument that the spec became more popular over time implies that it wasn't particularly popular to begin with, which directly counters the dude I quoted who said that "everyone thought MoP Destro was awesome the whole expansion".
In fact, Destruction got buffed in 5.1, buffed in 5.2, buffed in mid-5.2 hotfixes, and buffed in 5.4. That's not really indicative of a spec that "was awesome the whole expansion".
e: Sorry, didn't notice there were so many new posts.
Yeah, I've noticed I'm actually having a bit of muscle memory problems relating to the slower GCD. And also to Havoc not being a super-short GCD. But even so, with all the new things going on, talents-wise, the spec still feels faster to me right now because I'm operating on new parameters.