I don't understand, you should be able to slow down the clip to 50% without any choppiness if the clip is 60fps

With twixtor, if you're working with a tricking replay with smooth keyframing you should be able to get that far slower without any warping. Besides, it isn't always necessary to record THAT slow.

If you still insist on doing this, I'd suggest changing the camera angle between cuts so it doesn't look as stationary