What's really odd that I just noticed is that even when recording at 60FPS via FRAPS (to an SSD of course), the recording shows none of the microstuttering that I observed while actually playing... The showframegraph command didn't show any large spikes at all either. Yet, while playing, it's still very obvious that there is some occasional stuttering of some sort (again, that only just started with MTA 1.4).