Another method to consider is West Sytems epoxy for laying teak decks.
Thinner cuts of teak are used (about 1/8"), which give much less expansion & contraction. Also easier to bend. The teak is temporarily screwed down using a washer between the strips. The screws are then removed after the epoxy has set.
Rather than the painful process of using bond breakers and caulking, an epoxy/graphite mixture is used to fill the joints, sealing the screw holes at the same time for a permanent seal.
Less teak is used (lower cost and weight) and there is virtually no chance of leaks. It lasts just as long as thicker strips which require replacing when worn down to the plug depth.
See page 41-42 here for more details of the procedure: