If it doesnt need stitched then I just use double sided tape on my Arc, under the sail cloth repair tape. The tape I use is from Dimension Polyant and is a japanese tape call "kika sili". Look them up in the yellow pages, they are happy to send a role in the post fora small fee. It comes in various widths, I ordered 6mm but next time I will order wider 12mm,

Also I have found that after coating the kite with a water repellant the double sided tape doesnt stick so well so you may need to clean the area with metho or similar.

I have had to seams give way in each tip at the front edge on each wing tip, the only solution was to sew, just unpick the rear and feed onto you mums or wifes sewing machine and go for it.

it sounds like an area that was problematic on the old arcs

"newer" s-arcs had that area significantly reinforced. you could probably get ur local kite repair mob to sew in a ~6 inch strip of canvas/heavy cloth to support the area