Yes, it's very handy that he keeps your measurements on hand! Mine haven't changed since last time I ordered but I am pretty picky so I figured I'd get another muslin just in case.
Personally, I think his original pattern looks right to me. I think maybe the tapered look has to do with the fact that Brad Pitt has broad shoulders. If you also have broad shoulders I imagine Jonathan's cut looks about right. I think the lambskin plays a role in that as well. I'm curious to hear what you think though – my opinion is only founded on pictures.
I could see MAYBE getting some tapering due to distress if the jacket stretched in that way but personally I think it's unlikely. I'm no expert but that's my line of thinking.
If you could post pics of the tapering that would be awesome!