Personally, I think the "dangers" of grease on a spindle taper is pure BS in practice. There is no way a greased taper will allow the crank arm to sit further on the spindle than a non-greased taper. It all comes down to how tight you torque the bolts and the hardness of the flats on the crank arm and spindle. If a crank arm is sitting too far on the spindle it's because the flats on the crank deformed because the fixing bolt was over-torqued, not because there was grease on the spindle. A square peg doesn't fit into a round hole just because there's grease on it.

With all due respect to Sutherland's book, that's pure conjecture on their part.

Still, for the last year or so I've used Teflon tape and no grease on the tapers.

Stronglight cranks are soft. Don't over tighten the fixing bolts. How do I know how tight is tight enough? The same way I know when my steak is done. I just do.