I might also point out that the method in question is not nearly so
guestimated and vague as you state. Successful DR navigation depends
largely on 1) accurate and detailed planning; 2) careful and accurate
boat handling; and is also affected by 3) unanticipated factors, which can
be ameliorated to some extent by (1).

so, guesses become precision by planning to make guesses?

only if the laws of physics are wrong.

wanna explain to the aviation world, the world of physicists, or the nautical
underwriters how *your* world is an improvement over reality just because *you*
want it to be?

you guys who claim the laws of physics don't apply to boats because you don't
want them to shoudn't be allowed on a boat not painted Day-Glo Orange with a
DoNotRescue marker on it. Let Darwin fix the problem.