Anybody that doesn't see how important Hollins was to this team's series victory, simply does not have a good eye for the very many vital ways that a player can impact a basketball game.
Sometimes one player hustling and managing to tip the basketball out of bounds, forcing the other team with very little time left on the shot clock to inbound and rush up a shot that is far from ideal, perhaps due to the fact that the defensive pressure is now more focused on every player on the inbound attempt.
A simple situation like I just described can be the difference between a won game, and a great game, but a close loss in the end. Do people realize, for example, that the Dallas Mavericks didn't play so badly against OKC in that series? They lost game 1, game 2, and then game 4 because of the little things people take for granted. If one player on the Mavericks makes the right player for the Mavs at the right time, who knows where that OKC vs Dallas series is at right now.
You have got to be able to see value, and clearly KG and Pierce see value in someone like Hollins. KG and Pierce wouldn't recommend someone they didn't feel could really help them out.