I don't necesarily disagree with your analysis...if
I understand it. But the idea of waiting to kick out
of a full crab to a full slip(or however you want to
word this), does not seem to me any improvement of
using a combination of both...particularly in strong
crosswind conditions.

Personally I think one should fly whatever he/she is
most comfortable with...because rarely are short final
approaches the same in extreme crosswind conditions.
And I think for the most part...these strong crosswinds
are not seen much during training...rather we self-teach
ourselves the technique that works best for us. Personally
my preference is to not practice new techniques when
I have something that seems to keep me on the runway
when the crosswind is 20+.

On the flip side...I see some instructrion manuals
that recomend no crabbing whatsoever.