Thus even if the hours flown estimate is "systematically"
misestimated (i.e. is inaccurate) it would not invalidate the conclusions
of the trend analysis conclusion. Yes?

Yes.

The BTS study showed subsidies so
large that...

I haven't read the study so I can't really comment on it intelligently.
But like the difference between precision and accuracy, there is a
difference between pro-rated costs and marginal costs which needs to be
taken into account. One must also consider who benefits - it's not just
the immediate users.

And even if xxx were subsidized, that's not necessarily a bad thing.

Jose
--
Money: what you need when you run out of brains.
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