[Amps] GG in Class C?

[Bruce Brackin]

Is it possible and/or feasible to put a grounded grid linear into Class 
C?  Reason I ask is my old Tempo/Henry 6n2 is used almost exclusively 
for WSJT modes and they all do fine on Class C since they send single, 
sequential tones.  Amp is configured as push-pull on 2m and parallel on 
6m.  Current biasing arrangement is single 10v, 50w zener in cathode 
circuit.  I would think the efficiency would be much better in class C 
if that is possible and would seem to help the 3CX400A7/8874's along.  
Searches and old handbooks haven't been much help.  Plenty of info out 
there on tetrodes and biasing but not gg triodes.

Thanks - Bruce, N5SIX