When I read how the Two Row Bind Off is worked, I found myself baffled as to how this was supposed to be stretchier than the Chain Bind Off. You work across the first row of the BO passing the knits over the purl stitches. You work across the second row by slipping the purls and passing them over each other. I can’t imagine how that is supposed to make it stretchier than simply passing stitches over each other as you work across one row as with the Chain Bind Off. It’s just weird.
It does create a nice edge. The Knitter’s Handbook suggests using it when adding fringe because it creates nice little gaps. I could see the Two Row BO being useful in situations that use ribbing to prevent curl instead of for its stretch like on a scarf, but there are better BO methods for something like that.