To me, there is an issue of how the date is stored and how it's displayed. That is, I have dates like 1 1650, which I take to be March 1650 new style. (It's not clear to me if someone would have written 12 1649 on 24 March and 1 1650 on 25 March, but that is for a different thread!)
Optimally, there would be a page (or hideous popup dialogue) where one would input the date to see how it would look in other forms, e. g.,
Enter the date: _________________
.....This would look like 1650-03-11 if we projected the modern calendar back
.....This would look like March 1 1649/50 in England at the time
.......This might look like 12 1 1649 at the time if anyone understood that stupid system...grrr!
Uber-optimally, checking a Displ. box would make the dates show in that form
I don't think it is necessary to do much more than this. If there is some contingent that has a lot of date issues, maybe add them. I don't think there are too many people labouring under the Napoleanic calendar, so Julian would serve a great many needs.
The point would be to get people thinking about date conventions. Unless you are at a courthouse or graveyard or have an old bible with consistent date notations, there is not a lot of hope for accuracy. Seeing how a year or month can change dramatically, might help future transcriptions to be more thoughtful.
(funny observation at the bottom).
Thanks for reading this!