While there's some quality fodder there, I couldn't get beyond this line:

"I’ll bet that the time-to-signup isn’t an important anxiety factor."

This isn't the only reason that sign-ups have been pared down; the current trend of thought on the matter is that it also reduces barriers to conversion.

Engaging your audience without making them jump through numerous hoops is a great practice, even if that means the occasional company adopts the practice a little too quickly before the rest of their process is fleshed out. I'd certainly prefer that to the alternative, where I've invested a great deal of time with a long form, just to have the same end result, 'and then what?'