Move title causing serious performance problems

In one of my video editing projects I experienced increasing performance problems in FCPX, like stuttering playback, taking ages for characters to appear when editing text, response times of 5 secs or more between mouse clicks, etc. to a level it became unacceptable.
Because earlier projects never gave such serious problems, I tried to figure out what was different in this project and eventually all pointed in the direction of the "move" title, I had never used before but used it extensively in this project. So i decided to replace them by ordinary "Basic Thirds" and along the way performance got better and better. After replacing them all, it is all nice and responsive again.
So: don't use the Move title

I'm experimenting with the Move template (build in/out catagory) and having no issues at all. I'd start looking at other things. Be sure background rendering is off. Verify you have enough free space on your drives. I'm putting it on some complex comps and not having any issues at all. The Slide In and Slide Out behaviors from Motion may be a little more stressful on your system than other behaviors in other titles, but I don't see it being that huge. Tested two Macs, one a 2015 rMBP, no issues on either with Move.

Dinky wrote: … don't use the Move title

I'm not doubting your experience, but don't follow your conclusion:
tested Title/Move on my antique, under-powered 2012MacMini = smooth like butter, even a dozen of Move Titles stacked in one timeline …

I'm with Ben: the culprit should/could be something different … would you like to share a screenshot of your timeline…