Skinner adds depth but adds very little that Davis doesn't and I don't think having him on the roster would add enough of anything that we still wouldn't have been looking for another player.
Skinner adds a defensive shot-blocking presence that Davis doesn't have.
Moore I can't see what he adds besides depth. If Skinner wouldn't be the answer to play against bigger players, neither is Moore.
In the end, they're very similar players. Foolish not to sign the one who was available to go to the training camp.
While I agree that Skinner would be a decent guy to have, I think that Moore absolutely adds something to this team more than depth.
The problem with Davis isn't that he doesn't block shots, its that he doesn't have the length to bother certain players shots. Even though Moore doesn't block many shots either, he does bother them.
I think that Davis and Powe (especially Davis if he continues playing the way he has over the last 2 months) will be getting the majority of the backup big man minutes, and I think they will give you in many ways more than what we got from PJ last year. The only thing the C's really needed was another option who had the length to deal with longer, athletic players who give Powe and Davis problems (Odom is probably the best example).
Davis has shown that he can do an excellent job on big, strong guys, by throwing his weight around, and not allowing them to get position in the post. But he has struggled against guys like Odom (Josh Smith is another example). Moore will be able to give those guys problems, and that is really all they need.