all the other questions have been adequately answered..... but....

example, once I tried to force the Grob on the runway but she wasn't
ready to land yet. I was too high but didn't properly use the
divebrakes, thus landed her with numerous bumps the full length of the
7700ft runway, inducing hysteric screams by the owner of the flight
school - meaing more dual flight instructions.

That's why we enforce the "low energy method" to land the Grob103, too many
people try to "land it before it is time", and end up inducing an
uncontrolled PIO down the runway.. get broken tail booms that way, or flat
nose tires and squashed nose wheel attach points..

Fly a controlled stabilized approach, as directed by the POH, normally best
L/d +1/2 the wind speed (up to a reasonable speed of course), less than 1/2
spoilers in the round out, don't close them all the way or you will balloon
in the round out and gain about 10-20ft of altitude, nose up, about the same
as the take off, and just let it settle onto the runway,

If it is not settling, NEVER push the nose down, slowly increase the spoiler
deflection until the slightest hint of additional sink rate and freeze..
hold the attitude and the spoiler position and it will settle..

This assumes that you have rounded out at a proper 1-2 ft altitude, assumed
the proper attitude and have the speed "on target", round out at 10ft AGL
and you are starting the approach from scratch and could be facing a very
high sink rate to impact... take that you nasty runway...

Experienced pilots can roll it on about 10knts faster than needed.. but
they've got the "eye" and the coordination to not over rotate in the round
out and keep the main wheel on the runway with the nose and tail wheel
aloft.

Glad you are joining the realm of "motorless flight"

BT