Having created my own test version of a Tri-Flash with some clamps, I found that it is a magnificent way of having great, soft and natural light.
The backlight was provided by a single flash unit with a green gel, shooting straight back in the camera. Main light by Tri-flash through umbrella.
Also it is great to give a bit of extra punch in group portraits.
However, to keep it simple, and giving my gear the best, I ordered a Joe McNally Tri-Flash. Can’t wait to create more with this tool!