I do think White is more likely to stick than any of the backs we had last year, outside of maybe Ahmed. I also think that some people automatically write off anybody who is an UDFA. I find that opinion to be unsupported, particularly on a team that has Needham playing a ton and a head coach with a reputation for being a run game expert, who was brought in, in large part to fix the run game, and comes from a system notorious for finding late draft picks and UDFAs at the RB position.
McD has stated that he has specific RB criteria that he has found to be successful in his system and that he explained those to the scouts so that they would know what he was looking for. It's logical to assume that the four RBs he brought in likely meet those criteria. So when McD is asked, "who has impressed" and he mentions a RB by name, I'm not inclined to write it off as nothing.