I know what you mean broric. For film or even video this makes total sense because the framerate you play something back at is constant. 30fps, 24fps, or whatever the format you're using dictates the playback rate to be. So for slow motion you record at higher framerates so that when it's played back it plays back those same frames over a greater length of time.
That makes sense for film or even video recording.
But in MediaTracker we simply have a time factor indicated with a number. "1" indicates realtime playback. "2" is two times faster than realtime playback. "0.5" would be halfspeed.
These numbers give the desired results when playing back the clip in the replay editor.
However, the timespeed clip doesn't work if you save the replay with the timespeed clip in it and then go and play it back by selecting the replay and choosing "view".
And of course I mentioned about the problems with doing a video.
But my original report was a little wrong. Adding slo-mo clips is not actually speeding up the video.
It looks like the game is simply ignoring the timespeed clip. It's not actually speeding it up when rendering. That was just an illusion that fooled me because of the quick camera movements.
Here's a video I've made to compare different settings using both the in-game renderer, as well as recording with fraps as I played the clip in-game in the replay editor (as that's the only place where timespeed clip seems to work)...
MediaTracker: TimeSpeed Clip Test
By the way, for timespeed to even work at all... you have to first delete the clip and track called "Time" which is saved with every replay.
To summarize my report: Timespeed clip should be recognized by the game for intros, outros, and especially for rendering videos out of mediatracker.