Thanks y'all! Yeah this question came to me because I was preoccupied with the parameters on one of the Pod Go's compressor effects, with one default value being -37 dB (around maybe 30% spot on the bar). I was trying to compare it to a general compressor settings guide which simply says "4 O'clock for this tone, 2 O'clock for this other tone."
But yeah I totally haven't considered the nature of logarithmic vs linear values, max/min default positions, etc etc. If only it was easier to specify a value on an actual pedal.