I am still puzzled...
I checked out my archive and looked through all the catalogs and stuff, and in the early 90's a sensitivity of EV-4 by far was extreme.
But I also found one dubblesided photocopy out of some magazin or catalog, I dated as 1993. And it contains (without importer or manufacturer stated) an ad for Calcu flashes.
For the models Flash S, Flash II, Light X and Light XP.
The title says "Digital Precision for an utmost advantageous Price"
There are hints at metering in the dark, but no wording of any kind that I would expect for a meter that is by one magnitude more sensitive than even the two or three most extremely sensitive competitors.
That likely was the reason that I read what was given at the small-letters section not as sensitivity but as min. value on scale, as an error of the translator.
I filed that Calcu photocopy at the far back of my light meter register where the obscure or no-name ones sit. And funny enough just the next filed item is a page out of the catalog of a german dealer/importer of obscure stuff who got the sensitivity of the Polaris meter wrong by 5 stops!
Just the usual error concerning what I explained above.
Thus can you confirm that the Calcu Light XP actually is that much more sensitive as stated?
(Best tested against competitors.)