@snood,
Coward has a lot of different dimensions and meanings to it, and there are certainly plenty of things that he does that people can legitimately describe as "cowardly" but I think his temperament has the opposite problem, that he doesn't have enough healthy fear of failure, censure etc to keep him in check and give him a better filter.
Ultimately this is just semantics though, it's hard to pin down what "cowardly" actually means to different people.