there is an alternitive. Frankley I don't like the merge edge tool. So I just select 2 vertices on the same side, go to Edit Polygons>Merge Vertices> option box. Then just crank the settings up to 10 (I like it high), and click accept. then just select the other vertices, and press g (Repeat command). That should work. If not, I'll post a pic for you.
Imagination is more important than knowledge.