The team will need more than that. Squads like Georgetown and Seton Hall and Rutgers have 4+ man rotations in the post - they'll stay fresh and be physical.
I don't think it'll be enough. If Gathers is actually thinking of coming for 2011, and comes to St. John's, that won't be enough - but it will be much closer.
Seton Hall (Pope and Johnson) and Rutgers (Biruta and Jack) may have guys in the post who could cause some trouble, but G'town's post men doesn't do it for me. Not to mention, I don't really four bigs from either Seton Hall or Rutgers seriously being a threat. IMO, two at the most.
IMO, I believe Pelle, GG and to an extent, Sampson, will be able to hold their own. If, we were to add Gathers for 2011 (which, it seems like he's gonna stay in the class of 2012) then that would be enough going forward.