Here's my 2 cents. At 100+ KGs I also have a 17m 2013 Edge. I ride a T5 140 Here is me riding in 11 knots of warm wind.https://www.youtube.com/watch?v=zTaTJu1 ... G8_J0MTEsg
The 2013 Edge goes up wind better than most kites out there or it wouldn't be winning all the races. I was riding this day to the point where my kite was not flying over my head and dropping back in the window. So here are my tips for going up wind.
Kite Check board need a flat board with little rocker like the T5. If on a Shinn I would not be going upwind unless it was a 150 King George.
The apparent wind thing is true but all it means is don't choke the kite so no big secret on how to fly the Edge. Either bare off to build up board speed or keep on a plane in the lulls and pull in just enough not too much or you will kill the speed.
Next stance. for chop and ultimate upwind ability this works best. 1) bend your knees and be in a position like you are just about to sit in a chair but not quite falling into the chair. What this does is stops you from digging in your edge too much killing the power. It equally balances your weight on the board and the kite pulling you up. Knees are bent to absorb chop and keep the board connected as much as possible to the water or each chop you bounce over with take you downwind.
2) apply 90% pressure to back heel and 10% to front foot to guide the board. This again prevents you from digging both feet into the edge and killing the power.
3) Like Tone said get on a plane and once on plane ease out and don't choke the kite.
You'll be unwinding everyone!