[nsp] Stub Area design question

[Dan Armstrong]

I have a desgin question about IGP routing protocols in a stub area.

Picture a generic service provider network.  Several access routers to which 
customers are attached.  All of them dual homed up to 2 distribution layer/
metro core routers.  All of the access routers are in the same ospf area.  
Each city (usually comprised of 2 Metro POPs) is 1 OSPF area.

The area in which the access routers are is an nssa totally stub area.  I just 
want to inject a default route from each of the distribution layer routers 
down to the access routers.  I want to advertise the C and S routes UP from 
the access routers, I redist static subnets, redist conn subnets and we're 
good to go.

The only thing about this design that bothers me is that since all of the 
access routers are in the same area, they all get each other's intra area 
routes.  Access router A can only ever reach access router B through the 
distribution layer anyway.  Each access router does not care what blocks are 
anchored on other access routers, they just need the default route(s).  

Should each access router be in it's own area?  Would having a crapload of 
ospf areas on the distribution layer routers knock some limit over?  

Could I write a bunch of messy route maps to handle this?

Am I missing something really dumb and obvious?

Thanks,
Dan.