Hello Jason,

We had similar requirement where applications such as biztalk, sharepoint are restricted to use MAXDOP=1 but on a shared server there were many other applications too which were performing badly without parallelism. So we created a classifier function which segregated the workload depnding upon the login name, set MAXDOP=1 for workload group and routed all the incoming traffic from sharepoint and biztalk to this workload group. And we set Degree of parallelism to 0 at server level. During a month's testing it did not create any problem and we're looking move into production sooner with this setup.

However, You need to be careful with what you use to classify the workload. For me database name is the best bet but you can't use DB_NAME() in classifier function so you need to rely on some other parameters like login name etc.

Thanks!!

-Yogeshwar