Rising/Shaping Problem For "Sweet Potato Loaf" from "The Bread Bible"

I'm sure lots of you folks have made recipes from The Bread Bible by Rose Levy Beranbaum.  I have a loaf doing its final rise in the pan right now, but I had a problem with its "volume" after I formed it and put it into the pan.  Technically I don't know what the problem is.  Maybe it's just how I shape the loaf.  For the recipe, there's a first rise, which goes just fine (doubles and all).  I do the envelope folding and it goes back in the bowl for the second rise (again just fine -- doubles).  But after that, when I shape the loaf and get it into the pan, it seems completely deflated (okay, not completely but a lot).  The book says it should come up 1/2 inch from the top of the pan -- mine is closer to 2 inches from the top.  It will eventually rise above the pan top, but I don't know what I'm doing wrong.  I had the same problem with the "Banana Feather Loaf" recipe.  Both seem to be very "wet" doughs, but I don't know if that would cause what I'm seeing.  Any ideas?

I don't punch it down or try to deflate it in any way.  Just the folding to redistribute the yeast and gas.  This is the first time I've done the sweet potato loaf, but when I've done the banana feather loaf, it eventually turns out just fine (seemingly for a beginner) even though it takes a while longer for the final rise after being shaped.  I just don't know if I'm doing something wrong or if this is just the way it is.