Quote:
should the catalogue value be higher proportionately?
I can see why you might expect that to be true, but it turns out that the respective CVs are not proportional, at all. (In this era, German coil stamps had a control number on every fifth stamp, and this held true across all of the denominations.)
In the lower denominations, with a lower CV, the
Nummer stamps have a 3x to 4x premium; the higher denominations, with a higher CV, only reflect something like a 1.3x to 2x premium.
For what it is worth, the preferred format for German coil strips is a strip of 5 with the control number on the middle stamp.