For comparison with my numbers, opening a video file on the Client from the Server with no conversion takes around 2 to 3 seconds, with TS files fastest, and AVI files slowest of those I tested. Gigabit Ethernet connection. MC25.0.31 on both PCs. ROHQ of course. AMD card on Client.
Side issue:
While testing the speed by repeatedly starting a video, closing it, then starting it or another video within a short time, say less than ten seconds, I could repeatably crash (not lock up, crash) MC.
Actually, the crash only seems to happen if I only play a video for a few seconds, stop it, and then try to play a video again afterward. Even waiting 15 seconds or a bit longer didn't clear that issue.
Log with Crash Dump on OneDrive:
https://1drv.ms/u/s!AE8KH39qCkz1idY2