I used to use 2 straps from the transom to the trailer, hold down the bow using the winch strap to the tow eye/handle, and have a third strap as you do in case the tow handle failed.
In retrospect, I could have rigged something up to go from the handle straight down to the frame to keep the bow from lifting, but the over-tube strap does about the same thing.
Some folks frown on a strap over the tubes (wear point, and not real useful when somewhat low on pressure), but at the time I didn't see any way around it.
jky
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