What will happen if you do not install a garbage disposal directly to the drain pipe?
Okay, all kidding aside I believe what you are talking about is the hookup with 1 sink basin vs. a double basin sink into a single p-trap. You will want to use either a center outlet continuous waste drain, or, an end outlet continuous waste drain depending on where the sink drain is located. The disposal will go into 1 side of the tee and the other sink basin into the other side wher the 2 will be combined into 1 pipe to the single p-trap. The sink having one trap for each side would be optimum but if your house is not plumbed that way this is the next best thing. The continuous waste tee does have a baffle in it that directs the flow down to the trap this does restrict the flow somewhat and if the disposer side of the sink ever cloggs while the other side is okay I would start by looking here as long as the disposer is running.
