Normal.dot versus blank document template

I have been involved in several discussions regarding this recently and
would like to try and clear this up. My firm hold the normal.dot (and
all other templates) in a central templates folder on our network.
Each user has a copy on their C drive which updates every day when they
log on. This means if the network crashes they can still work with
their template(s). Normal.dot contains all of our macros, styles,
autotexts etc. When I update I simply update the master version and
this is replicated to each pc. This means if a user's normal.dot gets
damaged it can be copied from the master, and if something goes wrong
with the master I can copy my (or someone else's c drive version).

This seems to work well but everything I read tells me we shouldn't use
normal.dot as our blank document - can anyone tell me a good reason
why we should change?

thanks