Last month I reported on the 2 before/after images here. Merging three 4's, 5's, 6's and M's yielded 1588 points. At the time I assumed that would be the highest possible point combination. I was very wrong.
A few days ago something new turned up. It didn't even occur that this could happen, or I would have taken before/after screen shots. I had another combo lined up: two 1's, two 2's, two 3's, and two 4's. An empty space would connect them all. I got a single 1 and placed it in the center. As expected, it made the other 1's a set of three and they morphed into a single 2, which merged with the other 2's....you get the idea.
Here's what's unexpected. Below everything were two 5's. The 4's turned into a 5 and then merged with the 5's underneath to form a single 6. That 5-plex combo yielded over 5000 points. Which makes me wonder what would have happened had there been two other 6's nearby.