[Amps] Henry 3K-A 'gotchas'?

[Jim Barber]

Any fatal flaws or (significant) bad design decisions in the Henry 3K-A?

After squinting at the schematic available at the BAMA site for a while 
what I see so far is:

(1) A rather unusual "manual" soft-start circuit

(2) The grid metering is done directly, for some reason...?

(3) Operating bias looks to be established with a zener, but I really 
don't understand the combination of RF choke and feedthrough cap that 
appears to short the filament transformer center tap to one side of the 
filaments... I must be looking at that one wrong!?

Any comments, stories etc?

Thanks,
Jim, N7CXI