Comment by branko_d

> looping through cursors, making business logic decisions, calculating things, etc.

Interesting. Can you share more details about the "non-data" processing that was done? Were they doing heavy mathematical calculations and such?

> change in business logic that would normally only need to update application code, now invalidates the stored procedure's cached execution plan

As for plan cache invalidation - the most extreme case I saw was on the order of 5-10s. Basically, it depends on the size of that one stored procedure - not on all other stored procedures that may call it or be called by it. What was the actual time that they got?