I took my Kovea Spider stove, Evernew 1300ml pot, and a Ti-Tri cone out.
First off, the pot stands of the Kovea Spider are plenty big to support a 1300ml pot.

When I put the Ti-Tri cone in place, I noticed a couple of things:
1. The pot stands push the pot up above the rim of the the Ti-Tri cone about 1 1/16th inches (about 27mm).
2. The hose of the Spider has to be fed under the lower edge of the Ti-Tri, which causes the Ti-Tri to jut up about 1/4 inch (about 6mm).
Since the pot sticks up a bit (but not bad really), you will a) lose some heat transfer since not as much of the pot will be within the cone which causes exhaust gases to flow along the sides of the pot and b) you’ll lose some heat to convection since wind can now strike the exposed portion of the pot.
I suspect both of the losses described in “a” and “b” above will be minor. The pot really doesn’t stick up that bad. I think the Ti-Tri will probably be more efficient than my usual windscreen, an MSR windscreen, which has better height but doesn’t control air flow.

HJ
Adventures in Stoving