Ok, this is tough to explain so listen carefully.
- Seperate your Templars a good distance.
- Go to the other area where you want to go.(Remember to have the two Templars selected and nothing else)
- Click R for Merge, and then hold shift and right click over to the area.
- Remembering latency, press S to stop RIGHT before they merge, and they should stop and float across.
This goes for both High Templars and Dark Templars, just Dark Templars are faster so it's harder.