We have (had) under hood webbing tie down loops on a couple compact cars that most often carried a single boat. Having the front tie downs angled out /\ really helps prevent any sideways movement in wind or passing big rigs zooming past in the hammer lane, and actually keeps the driver’s sightline cleaner, with the ropes going off to the sides and not down in front to the bumper/tow rings
It gets to be 4-lines more occluded with dual tie down ropes in front of the windshield with two canoes racked. With four canoes on the big van eight lines presented an impossible forest of rope to look through.
I often have more than one canoe on the roof racks, and use a single line as a bow tie down to the bumper or tow ring. Not as good, unless the stern tie down is pulling in opposition the front tie along isn’t as effective in crosswinds and isn’t doing squat to hold the boat in place during a hard stop.
That single line serves mostly to instantly indicate “Oh crap, pull over quick, something ain’t right or tight on the roof racks”.
We busted a gunwale stop in high prairie winds with three canoes on the van, saw that line scoot sideways and pulled the heck over. Had a nylon belly line (nope, won’t use nylon ever again) stretch out enough in the rain that canoe hopped over a short gunwale stop. And etc disasters avoided with that visual aid.
I can’t see the bow of most canoes through the windshield of the Extracab truck unless I crawl under the glass to peer up, which is uncomfortable while driving. I couldn’t see two of the four boats on the van unless I stood on the hood.
I think I would know if a boat came off, but I have seen enough “LOST BOAT: My Stomperdomper XL came off my racks somewhere on Rte 123 between East Jesus and Nowheresville WVA” posted on whitewater boards and all I can think is “Hmmm, no bow line indicator?”.
