Why does outdoor gear seem to use the straight stitch almost exclusively and sailmakers use the zig zag stitch? I have to believe that sails see a decent amount of stress, would outdoor gear (tarp, tents etc) benefit from the zig zag over the straight?
My entire sewing experience is limited to a few hours yesterday on a borrowed machine, but I am keen to learn.

Good luck,
Red

I don't think that sailmakers always use a zigzag stitch. They may do so on light stretchy spinnaker fabric however, and that is for two reasons:

1) With fabric which stretches you need a stitch which can stretch too. Zigzag can; straight can't.

2) Any stitch localises the forces which can weaken the fabric, but a zigzag spreads the load somewhat. Ever seen a burst spinnaker? The sailors do tend to load their fabrics a bit more than we do at times :-)

Cheers