Did you ever find a solution.
I have the same problem in premiere. As soon as the mercury transmit is enabled the video stutters every couple of seconds.
I have the two monitors for the premiere app (DP) and then a 1080 TV monitor for the mercury transmit (HDMI).
There is no bottleneck in the system. GPU, CPU, SSD all running far below 100%.
12 core i7
64gb ram
Titan X
Lots of SSDs
Its smooth if i disable transmit.