Completely agree. Even though benefactor is right in that Hairston is more of an SF than an SG, despite him being relatively short, ideally the Spurs need another backup SF. I know his thinking probably is, if Hairston lacks the ball skills of a SG, then why wouldn't the Spurs pursue an SG? Because they don't need their backup wings to have tremendous ball skills. The ball is going to be in Parker's, Ginobili's, Hill's and Duncan's hands the vast majority of the time. What the Spurs need is role players who can defend and make open shots.
On top of that, between Ginobili and Hill, the vast majority of the SG minutes will be spoken for. Sure, for depth purposes they need another couple of guys who can play there, but technically Hairston and Temple are SG's first, despite the fact that on this team their minutes will primarily come at SF and PG, respectively.
I disagree. Maybe on an individual basis height isn't important, but when you're a team that's already undersized, specifically in terms of backup wings, it's not ideal for your primary backup wing (I assume Ginobili will go back to the bench, but I consider him a guard, not a wing) to be severely undersized, even if he is freakishly long.
Length to contest shots is beneficial when guarding similar sized players. For all Hill's length, that doesn't help him when defending Bryant. It would matter if his neck had two more inches. Again, maybe not individually (it's more of a case by case thing; like I said, T. Allen seems to defend bigger players fairly well for the most part), but based on the composition of this roster they need as much size as they can get.