We do practice that here.
But many places do not practice for this.
Full spoilers deployed ( to achieve symmetry) through approach, from
the point of unlocking through flare/round out and touchdown. The
typical error we find made by pilots in this configuration is the
tendency to "hurry" on approach, with extra airspeed, and not
understand how it will affect their glide slope.

It should be much less of a handling worry to make the glider
symmetrical, and control the approach in a regular configuration, than
to begin to think of all the "different" things you could do to
accommodate the asymmetry.

Just because there are several stories reported here of pilots who
either "didn't notice" their configuration issues, or handled
them with aplomb, remember that this is frequently Not The Case for
just as many others.

We also practice/teach approaches with spoilers completely closed, but
that is a different thread.

Cindy B
Caracole Soaring