I pretty much agree with Mr. Mountain. When I have too many polygons I go this way. select an edge convert it to a ring selection or use loop select. (MJPolyTools is handy) a loop I usually delete and then delete the vertices. ringselect is cool, cause you can then hit Collapse in the polygon menu. this way you can clean your topology pretty fast. with the split polytool change your loops and collapse again.
everything starts and ends in the right place at the right time.