[X4U] iSync and two users in 1 .Mac account?

[Steve Self]

I have an .mac account. My wife has an add-on email to this account.

Can I use this one .Mac account to publish-subscribe iCal Calendars  
between us?  Or does she need to have her own, separate, .Mac  
accocunt in order to do this?

I have tried various ways to get our calendars to appear on each  
other's computers over the years and each time it was too hard to get  
it to just work right... Any tips would be appraciated.

Steve