Run/walk - refuel -sleep chat to other people......no need for music. For me I spent 7 days obssessing about maxingwater and calorie intake and making the backpack as light as possible - if it couldn't be eaten,drunk or part of the survival kit get rid.
But if you have to revert to breastroke it isn't the end of the world. I've seen many triathletes take 30 seconds or so out in the middle of the race to do breastroke. No problem in a wetsuit if you get a thinner one in the legs to make them less buoyant. Advantages are breathing every stroke is great for people with dodgy sinuses, sighting the shortest route is easier and getting into the slipstream of other competitors as they come by is easier.
We shouldn't be put off from competing just because we can't crawl.
There is far too much emotional nonesense written about long distance triathlon. Especially the M-dot marketed ones. We choose to do it so if it hurts it's our fault. Don't expect others to think you're great just cos you made it harder for yourself. I used to enjoy watching the coverage on Sky TV and admit to being moved by some of the stories such as the Hoyts and Julie Moss but it's every event now and all driven by the M-dot Marketing department.