Time for a real world test ...
Conditions: Beseler 45MX, condenser light source, Stouffer 4x5 31-step tablet, 150mm Rodagon, Ilford MGIV RC glossy, #2 1/2 filter, D-72 70F 2 min
Prints were made at 4x5 (1:1), 5x7, 8x10, 11x14 and 16x20.
In each case the #1 step was metered with the Darkroom Automation meter. Time was controlled with a DA f-Stop timer. A total of 10 stops of exposure (meter reading + timer setting = 10) was given in each case.
The results are as consistent as I could ever do with test strips. All the prints were made with the same contrast filtration - results would be a bit closer if contrast were tweaked.
Time to find new exposure and set it into the timer after changing magnification - less than 5 seconds.