Outlook Filters and .OST size?

I foundout how toreduce the size of the OST filehere.

1. Right Click inbox, from the context menu click properties
2. In the Inbox Properties dialog click the Synchronization tab.
3. Click the Filter Button
4. In the "Filter Dialog" click the Advanced tab
5. After clicking the "Field" button select "Received"
6. Select "on or after" from the "Condition:" dropdown, and enter a value of "1 year ago"
7. Click "Add to List"
8. Click OK
9. Click OK again.
10. Click Send Receive...
11. After it's done syncing if you have an inbox that's over a year old, when you return to the synchronization tabthere should be fewer Items in your "Offline folder" then in your "Server folder" (under "Statistics for this folder")

This is supposed to reduce the size of the .ost file, especially useful when dealing with senior management that have inboxes that are larger than 1 GB. Are there any nasty side...