I think that you're both correct. Getting additional sight plane is about it. I thought that some one may try to tell me that a longer barrel may give you faster velocities or even that it may give you better/different patterns at longer ranges. I suppose that neither are true.
In the duck blind, I do not like to hunt with guys that use barrels shorter than 28 inches. The reason is that the shorter barrels and ported barrels can ring your ears. I realize you might be thinking I need to wear hearing protection and I do, but I have been rung by more 26 and shorter guns than I have 28 or longer. Thanks guys for your replies.