I came up with something that works pretty well, and isn't too far off.

47K series resistor from OSC2 (the output) to crystal, then 68pF to ground.
OSC1 straight to crystal, with 15 pF to ground.

Starts nicely, gets me close to the 12.5 pF crystal spec (especially if
you ignore parasitics).

KDS 32.768 KHz xtal, PIC16F84 running at 5 volts in LP mode.

I measure/calculate about .9 uW drive with this setup.

No way could I get it to start reliably and at the fundamental frequency
without high capacitance on the one side.

This is for a clock, so I wanted it to be as close as possible to the
crystal spec.

Probably running at 3 volts the series resistor would not be needed.

Thanks for all the input. Apparently Microchip documentation for
electrical specification continues to live up to its (not so good)
reputation.

Cheers,

Bob

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