Obviously, since Thomas' hands might not be his strongest assest, he would be able to contribute in other ways. Every RB has different strengths and weakness but almost any RB can contribute given the opportunity and situation.Pierre Thomas also played more and has had more opportunities.
Warner would argue that we can't tell for certain but if Bell's and Thomas' role would have been exchanged (Bell in Thomas' shoes and Thomas was in Bell's shoes) then Bell would be the one with 50+ receptions and Thomas would only have 2 or 3...