2008/10/9 WJhonson@aol.com:
delinking dates means the flag that we put in to allow standard viewing of the dates in British or American format ceases to work
This is, it seems, a major point as to why the linking system was abandoned - the date-standardisation wasn't proving to be more trouble than it was worth.
The discussion is exceptionally long and involved, and as I haven't been following it I can't comment in detail, but from a quick skim through it seems there was a general, broad, consensus that the dynamic reformatting of dates caused more problems than benefits. This sort of major change isn't done lightly, after all.
A summary list of the major known problems with date-formatting is here, and generally seems to make a pretty sensible case for deprecating it.
http://en.wikipedia.org/wiki/User:The_Duke_of_Waltham/Auto-formatting_is_evi...
"All in all, the auto-formatting of dates is a feature that negatively affects the appearance of articles and complicates their maintenance, with relatively minor benefits enjoyed by a very small percentage of Wikipedia's users."