At this moment I am testing the difference in this matter between 1.7.9 and 1.8.0. The gaps have not reduced a bit in the latest version.
I have tested both the scenario where I use four layouts and the scenario where I place al four videos (mp4, Full HD, 10 seconds each) in one layout. This does not make a noticeable difference.
We are using Intel Compute Sticks but the problem also exists on three tested Android devices (two different MINIX's and one device that was embedded into one of our displays).
After testing on my own desktop computers (one AMD A8/8GB RAM/ATI HD6890 and one Intel i5/6GB/ATI HD6970) I have to conclude that the gaps on these devices are nog significantly shorter than on the Intel Compute Stick.