John Gyakum 21 oct 2016: Precipitation rate as a function of vertical motion 
and air mass type based on there 900-hPa equivalent potential temperature

Basically, the x-axis is the air mass (increasing theta-e to the right),
with computed 24-h precipitation rates (mm) along the y-axis.  The two lines
show ascent maxima of about 1 cm per second, and 5 cm per second at 600 hPa 
(a parabolic ascent profile is assumed with zero ascent at 1000 hPa, and at 200 hPa).

The actual lapse rates assumed are all moist adiabatic, with assumed 100%
relative humidities.

What is clear is the very large precipitation rate sensitivity to ascent
changes as the air masses warm.

The static stabilities in all of the environments here were zero (moist
adiabatic), as I recall.

Fred's actual calculations of precipitation rate were for climatological
lapse rates of Continental polar, Maritime polar, and maritime tropical air
masses.

Albeit, the actual sensitivity of precipitation rates to air would likely be
larger than what I show, as the effective static stability decreases as the
air mass warms.

The three cases shown indicate very large positive anomalies of 900-hPa
theta-e values from climatology (shown by the heavy dashed vertical lines.