When I was working in MC 7, I applied LUT's in the clip source settings--that was the only way to apply a LUT in 7.0--and playback was flawless. After upgrading to MC 8.6, when I open projects originally created in 7.0, playback is jumpy when there is an additional video track with graphics and dissolves. But when I create a new project in 8.6 and apply a LUT as an effect in the timeline, playback is fine.
Did something change in the way LUT's are processed?