to piggyback onto vic's definition of 'keyness' i would suggest that the key met is not only the met for whom exists the widest expected variability of likely outcomes, but also for whom there exists the least-good backup plan, and therefore to whom the mets fortunes are the most tied. for this reason, neither ike davis nor lucas duda can really be the key met, as they are their own backup plans, followed by josh satin. and tejada cannot be either, as flores is a fairly passable plan b that many of us would like to see as a plan a (plus there's the whole debate of how good the likely upside can be). i think that d'arnaud or grandy are the key mets, as the upside for each of them is fairly high, the foreseeable downside could be low, and the lack of backup plans are equally apparent. i think the mets could swallow a struggling d'arnaud slightly better than they could a struggling granderson. if he's healthy enough to play, he's going to play - he's not getting benched in favor of duda or lagares. and while we expect good things from him, i believe, he's coming off an injury-stricken season and getting older, so anything could happen. if granderson turns into jason bay, teh mets are sunk, in other words. if granderon turns into vintage granderson, the mets will likely be just fine.