Doing this in my opinion fogs the issue of pilot responsibility for the
student, who can now easily start to believe that responsibility for the
safety of an airplane can be assumed in steps....or gradually, as the case
may be.

I disagree. It is not the responsibility that is transferred in steps,
but rather, the authority (whether self imposed or not). A pilot who is
endorsed for solo flight has full responsibility for the flight during
all its stages, but is not (typically) authorized to fly at night or on
instruments. That comes later, with experience (and often, with other
endorsements, which could include certification). A smart, newly minted
instrument pilot does not give himself the =authority= (I'm stretching
the word here but I trust you get the concept) to fly in convective
activity, the edge of icing conditions, or widespread low IFR; that too
comes later with experience (and equipment capability). But the
responsibility for the flight always rests with the pilot.

I don't see how letting a student (who has demonstrated his ability,
irrespective of the number of hours he has) taxi an airplane solo prior
to being ready for and endorsed for actual through-the-air flying
transfers only =partial= responsibility for the handling of the aircraft.

Jose
--
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