I think everyone either intentionally overlooked, ignored, or disregarded something in the third paragraph of the Yoshi P letter:
Patch 1.15a went live with all of the intended content (resulting in a bit of behest-induced fever on some forums, hehe), and the dev team is now on the next step in improving the game.
Perhaps Yoshi-P was of the opinion that Patch A was content and patch B is the game improvements.
I'm not saying I agree with that; In fact, I'm sure most will disagree. I'm just throwing it out there that perhaps, as Yoshida interpreted it, we got the content and now we're getting the fixes.
I don't expect that answer to make anyone happy, in fact I fully expect people to respond with "How could anyone think that was content?" or "There was no content, you're an idiot", etc etc (completely disregarding the fact that I'm interpreting what I though Yodhida meant, not saying what I think).
But I think we need to step back and consider that it is very possible that to Yoshi-P, what we got in patch A was his interpretation of "content".
I could be wrong. I'd like to be wrong. I'll know if I'm wrong in 11 days.