What is the logic of banging DOWN on a lawnmower crankshaft in order to
lift a flywheel UP?

In another thread, I asked about how to repair a lawnmower that hit an
obstruction and started running badly and then not at all. You guys
correctly ascertained it was a bent flywheel pin (mine was shaped like a
Z).

I tapped two holes in the flywheel with a 1/4x20 tap and easily removed the
flywheel with a harmonic balancer puller but only after I broke the intake
manifold in half trying to bang down on the crankshaft as I pryed up with a
pry bar.

In the end, I conclude that banging down on the crankshaft and prying up
with a pry bar is the wrong advice ...
(1) Prying up with a prybar can easily destroy the intake manifold, for
example ...
(2) Banging down on the crankshaft appears useless to me

My question:
Why do people recommend banging DOWN on a crankshaft when you want to move
the flywheel UP?

What's the logic?

The crankshaft isn't going to go down and the flywheel isnt' going to go up
when you bang on the crankshaft. It appears, to me, to be a useless
endeavor.

But, since so many people have said to bang DOWN on the flywheel ... may I
ask what is the logic in that?