I have scrawny chicken legs and have toured successfully with my BD. I was worried when I got it that living in a small downtown apartment with a small elevator was going to be a huge pain. It wasn't and I've enjoyed my BD a ton. A BD is far easier to handle than a bike + trailer.
If you can haul everything you need on a touring bike with panniers than I'd agree you don't need a BD, but I didn't realize what I could haul until I got my BD.
