That's the method I've tended to use, and it's worked great for me. The problem with starting from bootstrap is that it's incredibly well designed for specific

That's the method I've tended to use, and it's worked great for me. The problem with starting from bootstrap is that it's incredibly well designed for specific purposes, and there's a fear that changing anything is making it worst for the sake of difference. By starting with the interaction design, not only can you cut down on the elements used from Bootstrap, you can find uniqueness and utility without losing too much.