You may be right but I think it's very unlikely. Firstly, they already fit a jack into the same form factor and this wouldn't have been the first water resistan

You may be right but I think it's very unlikely. Firstly, they already fit a jack into the same form factor and this wouldn't have been the first water resistant device with an audio jack i.e. these were solved problems. I don't believe they would go through all this effort because they couldn't be bothered to work out how to fit an audio jack back in. If I were to guess it's either because they just like the idea of one connector that does everything (I get the impression that's what Thunderbolt was for). Either that or this a step towards a fully wireless strategy. As I quite like the idea of the latter, I'm going to assume it's that until evidence refutes it.