Starting Engine Question (O-320, Warrior)

My question refers to Warrior IIs, but could be about other
Lycoming O-320 and O-360 engines with electric fuel pumps too.

I've noticed checklists on some Warriors tell you to turn the
electric fuel pump ON and leave it on for starting, and others
tell you to turn the fuel pump ON, check pressure, then OFF
before starting.

The actual P.O.H. I've seen says to turn the fuel pump on before
start but doesn't even mention to check the fuel pressure to make
sure that the electric pump works. It doesn't say when to turn
the fuel pump off, except during the run-up to turn it off so the
pressure can be checked. All in all, the checklists in the
actual P.O.H. aren't very impressive and seem to leave a lot of
important stuff out. They don't even remind you to shut off the
cabin heat/defrost before starting to protect you in case there
is a fire during start.

So why the different schools of thought? It doesn't seem
necessary to leave the pump on for taxi, as the POH suggests.
But should the fuel pump be on while cranking? What does
everybody do?