I disagree. if we're gonna have the truncated-crown, narrow-margin shields (70 spec), then the height of the number should be diminished. on the 24" blank, the 12" numbers look terrible, while the 10" look passable.
I don't think you understand my point. The bureaucrats seem to insist on squeezing 12" Series D numerals onto 24" Interstate highway shields when they clearly do not fit properly. If having the letters 12" tall is the top priority then they need to change them to Series C numerals.
Note: last time I checked the MUTCD SHS, there was no spec explicitly allowing these 120% larger numerals onto an Interstate highway shield. A 24" shield is supposed to have 10" Series D numerals, not 12". Proportionately it scales on up from there for 36" and 48" shields.I agree 10" numerals do work better on Interstate shields, even set in Series D. Aesthetically, I prefer the look of state names on Interstate shields. But if the FHWA wants a neutered look on Interstate shields the 10" tall characters are going to work better. I would even be willing to bet the more generous spacing around the numerals would actually make these shields more legible than the current, very ugly shields with stupidly over-sized numerals.
The neutered look with 12" numerals just plain sucks. And this is my expert opinion based on over 20 years of sign design work on top of having a 4 year New York art school degree. Really, no one needs expert credentials to see that design formula isn't working. It just involves looking at the design results and being objectively honest over how it looks.
Basically, the Interstate highway shields looked fine from the 1950's and through the 1970's until some bureaucrat in recent years decided we need to squeeze the same size numerals used on US Highway and State Highway markers onto existing Interstate shield designs. I wonder if the person who made this decision flunked geometry in high school.
In order for 12" numerals to work properly on a standard Interstate highway shield the whole freaking shield must be redesigned to accommodate them.