I don't really and truly know you IRL, but I would say it will mess with your head something BIG time.
BUT: since this was an issue for you guys in the past, a 180 would be demonstrating desire/initiating, correct?
I wish there was a way you could do that *without* the full-monty. But I think all of it would be persuing. And another worry is, if he is truly detached from you in that manner *for now!!* and is in a bit of an A fog, then maybe it might come across kind of...unwelcomed too.
It's a gamble.
But I wonder how far a "Good god. *gulp* YOU look amazing. I miss ML to you so much" and walking away would go. Would it be horrible? Would it be good?