[OHM] Representing the Change in Tag Values over Time

[Rob H Warren]

This would break the OSM software stack. I'd like to do some modifications on it, but we have limited manpower. 

> From: Tommy Bruce <sunfishtommy at gmail.com>

> What About a key with 3 modifiers?
> We would have to completely redo the tagging schemes, but what if it was
> Highway=Tertiary=(Start date)=(End date)
> As for how to display features that have a double tag, I think it would be
> relatively easy to figure out.