Bob, I am glad you are a thinking man!
That would be a dumb idea if you sat there pumping away. What can you do that ensures the fuel and air gets sucked up into the engine?
A large number of O320/360 machines around doing it quite successfully if you poke around a bit.
Cracked primer lines are a problem as are the plungers etc.
Done right the new old method does everything it should and nothing it shouldn't .