I run mine in W all the time for the same reasons you mention. As far as the "self adaptation" I think the transmission has a pretty short memory, like just the last few trips, so any previous owner should not be an issue. The specifics of how that works were in a post last year so you could search if you are really interested.

Mike

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra