I'm just telling you what I have seen.
You do capture, but it's not enough. Think about it. In an ICE, od you get better mileage on a flat road, or a road that goes up 1000 feet and then down 1000 feet?
Flat road. Because of friction (?) you can never fully recover the losses. Same in a hybrid.
And look if it ends up being break even or a little better, you still have to recover the extra 10k you put into it.
The other thing about a hybrid is that to really rack up the numbers (50mpg) you have to learn how to drive it. It's a bit of a PITA to do, and if you are really maximizing MPG you risk pissing off the guys behind you who are rolling coal.