That's great to hear, thanks for checking and sharing. One can only go so far self coaching, and being in an environment that mixes things up, you break through those plateau's. Masters really means "adult swimming", important for swimmers to join and not be intimidated by the word "master" or the environment. I would hope your coach recognizes the foundation he built mostly on his own where an experienced coach can easily shape.
Whether six beat or two beat kick, he's got a kick timed with rotation that connects the core and whole body movement. I have come across many seasoned masters swimmers who think they have a '6 beat kick', but it's really just an poorly timed flutter, often kicking that inhibits rotation and its momentum; they had no idea the kick is actually timed with rotation. Whether 60 or 75 spm, he's smart enough to know which is working for him given his skill set and distance he's swimming in triathlon.
Is your masters USMS sanctioned? I assume so if you are racing pool events. What's your team name? I'm So Cal Tri Masters, LA/Sherman Oaks, CA. Let me know your team and I'll look you guys up. If you're ever traveling rhrough LA, always feel free to drop by to swim as a guest. I've had quite a few USMS from around the country stop in for a swim while traveling.