Conlang, Glossolalia, daiin pronounced

[Jorge_Stolfi]

To be extremely clear, according to the data there is a 0% chance of a date from 1005AD. The absolutely oldest it could technically possibly be is from around ~1300AD. The oldest it could reasonably be is ~1350AD, although this would still be very unlikely.

Agreed.  An error that big would require a major bungling, like mixing up the VMS samples with those of some other book.  Or the technician bumping on a dial and throwing the calibration of the equipment completely off scale. For all four measurements.

However, the VMS could be a copy made in the 1400s of an original created in 1005AD.  That could perhaps explain the cheap vellum and amateurish scribing, which seem incompatible with the amount of work that would have gone into composing the contents.  It also could explain some egregious scribal mistakes, like the rosary beads turned into tennis balls and the urine exam jar turned into perfume bottle on f85r2.

 (I don't think it is the case, but I don't see how this possibility could be excluded.)

All the best, --stolfi