If the calculations are based on the Global field, yes, it will resolve different for each user.
On another note, what are you using to sort on? If you are actually sorting using an unstored calc ( not entirely sure from the description ), you will want to field test that with a lot of records. Performance will become a problem if that is what you are doing.
Thanks for that feedback, Joshua. That was my hope.
I will be sorting on an un-stored calc field. The application will not have too many records in the portal, so I don't think performance will be a big issue. I will do some checking to make sure, though.