try this....
Most formulas were developed before the days of clipless pedals. Both pedal and shoes were thicker in those days, so the formulas need to be adjusted accordingly. Add to that, the fact that most people under measure their inseam, failing to apply saddle-like crotch pressure and you don't get much accuracy. FWIW, the formula suggests .883 times inseam.
The goal is to produce approximately a 30 degree included angle between the upper and lower leg, at the bottom of the stroke. One of the biggest obstacles to doing this is the fact that foot angle changes the leg extension. A rider whose natural foot angle is more heels up will have a taller saddle than someone with the same inseam pedaling with a more level foot.
As a starting point, try adjusting the saddle so the foot is horizontal at the bottom of the stroke, with the leg locked straight. From this point, raising the heel only 2-3cm will produce the desired 30 degree angle. I pedal without much rise to the heel, so I set my saddle a little lower. A heels up rider might want the saddle a bit higher.