portisfan24 wrote:So I guess my question is why isnt this done more often?
Probably because the IDP format itself isn't all that common yet. As the number of IDP leagues continues to grow, I'm sure we'll see hybrid formats like this (and other nonstandard setups) increase.
Aside from Guttpuppy's point, there's nothing wrong with using both IDPs and team defenses. To eliminate that problem, you could always limit your IDPs to teams whose defenses you have on your roster, creating a new strategic twist. As the Pupp said, it's all a matter of taste.