Charles is suggesting that because the chip once existed (ie before the name was scratched off) that it is a legitimate entry.
In my opinion that is absurd.

The chipguide should reflect what is currently known, not what might have possibly been known 75 years ago. I completely agree with you that without qualifying statements it devalues the chip should it ever be found. I can cite various examples where high end collectors have been put off making serious offers for unique chips because of the appearance of that chip in the guide (contributed by someone other than the owner of the chip). In some cases the scan had been enhanced which gave the impression it was not the same unique example. Quite the opposite of being a help to the hobby, this is very detrimental.