I actually managed to figure out the bimmini twist from Lou Tabory's Inshore Flyfishing. Then saw some slight variations on a bluewater trip down Cabo way a few years back.
Last year at the Lefty Kreh day, he showed us how to finish the Bimmini off in a very neat way - instead of making the usual 5 overhand turns around the doubled line, make 9 or more and then "Unwind" the turns which creates a kind of whip-finish. This makes it easy to tighten the locking turns whithout the annoying "stacking" that can occur with the standard method.
Back in the UK where a Bimmini is a Cocktail or brand of swimsuit
, I've won a few $$$ in bets on the Bimmini being stronger than the mainline. "Impossible" they retort and fall for it every time.
You can even put a bimmini in 7x tippet - but probably knot for Bluewater applications.