I've noticed a lot of the early designs from the late 20s
and early 30s used cathode bias (resistors to B- off the
directly heated filaments) on triode RF power
amplifiers. Were they adding a small amount of
bias to make them easier to drive? Or, for what reason?

One other thing, I don't remember seeing parasitic
suppressors on early rigs; did the need become
evident when TV became popular in the late
40s? I know those early TXs could take off in
the nether regions

Pete