. The canopy edge would cut the straps? How? Why?
Yes. Perpendicular flat roof flat sides. Utility tie down rail was below the canopy. I used the rails to secure the straps. One edge was OK because gunnel overhung canopy. Wind would sea saw the sea kayak straps on far side. Lol. Just kept cutting away at strap at speeds over 70ish.
No room due to width to tie up (just under 2 kayak widths). Very limited budget. Ended up tubing racks with old steel tubes on $20 worth of u bolts/washers/nuts, four offcut timber ends and a cover of sikaflex. Worked perfectly then, bars 1.5-2m separation. No bow/stern tie Downs, 5 m kayaks loaded deck down.