I think the exact opposite. We have adequate cover at the back and up front. I think our Gaffer relies on Joe heavily in midfield, and you can tell how much he thinks of him whenever he is interviewed on ifollow. He often says, first name on the team sheet, 8 out of 10 every game, a managers dream. Put it this way, when he is fit, he starts, simple as, never on the bench, as the others you have stated have been from time to time this season.
Personally, I think Joe's absence will no doubt be like Mozza's over the festive period for some of our fans. Ie - you don't realise what he contributes until he's not there. I have no doubt he will be missed tonight and Saturday, and sorely missed at Brentford and Derby.