That 2012 season was fantastic, but Neal-Malkin-Kunitz was a stacked line. Guys that gelled well. Neal with the big shot. It might not have the name value, but the three parts combined into one of the best lines of the post lockout era.
For the record, Malkin was at 1.40 PPG without Crosby that year.
Without Crosby, the Pens were like most teams with one star player, load up a #1 line to max out their offense. I don't think that season needs any qualification of having unusually good chemistry as Malkin has already showed he could produce with any quality of linemate.
The "facing easier matchups" argument that you could claim for his other seasons, IMO, really only applies to the playoffs, most notably against the Wings where in both '08 and '09, Crosby was matched against Zetterberg and Lidstrom and faced more time against Datsyuk.
Malkin also went off during Crosby's absence in 2008.
His numbers speak for themselves; as high a peak as Crosby and Ovechkin but more inconsistency and more injury-prone.