OK, so it must be enough of a difference to warrant you wanting to use a SSD over a high RPM HDD? I would think you would be OK moving and pasting back and forth, AS LONG AS you install the game to the SSD so all the files and shortcuts point to that location for optimal performance. Then when you are done, copy and paste to another disk drive. But like I said, those seem to be unnecessary read/write actions. I mean if you are talking about 15-20 FPS increase, then that may be worth it. If you are getting 30+ FPS with a normal disk drive, those extra frames are nice. But it you are getting 50-60 FPS on a normal HDD, then adding those extra frames isn't worth it to me, at least, to bother with a scenario like this. Hope that helps you out, and good luck!
For me playing Dying Light, I have my game installed on and run from my 7200RPM 2TB disk drive. My OS is on my SSD. With my setup, I am getting 55-60 FPS on max settings. I even have a MSI GTX 970, with 4 (3.5GB) of VRAM.