May I extend this to every single Vulcan on Enterprise for the same reason? I swear nobody ever bothered to tell the guest actors that Vulcans aren't supposed to show emotions, because every time I see them they seem to be yelling angrily at a human.
And in an episode I watched yesterday, Archer asked T'Pol to read something over for him and she said I'D BE HAPPY TO. HAPPY.
FWIW, this is somewhat belatedly (and, IMO, poorly) explained away in Season 4, when lost writings of Surak are discovered and it is implied that this will have a profound impact on Vulcan culture, which is why 23rd- and 24th-century Vulcans behave very differently from 22nd-century Vulcans.
I'm only up to season 2 on my first viewing right now, so we'll see how I feel when I get to that. But it seems to me that the Vulcans of Enterprise still follow the same rules of logic and emotional suppression, so I don't know that they can come up with a legitimate excuse for some of the slip ups.
What slip ups? The Vulcans have always been arrogant jerks that never ever lived up to their own ideals - yet for some reason fans have decided that they're somehow perfect beings. See: "Journey to Babel", "Amok Time", "Yesteryear", STV (aliens are allowed on Vulcan, yet they banish Sybok because he doesn't follow their lifestyle) and STXI.