[Amps] Need for input tuning circuit

[Bill Turner]

Consider a grounded-grid 8877 HF amplifier.

I understand the need for an input tuning circuit to maintain
linearity operating SSB, but what if the operation is CW or RTTY?
What if the 8877 is driven directly from the transceiver's output,
using the built-in antenna tuner for impedance matching?  Are there
any drawbacks I'm not seeing?

All comments welcome.  

--
Bill W6WRT