Hi Voltmatic! You must have had that power board that I made a slight booboo on. Those 3 holes are nothing. Just ignore them. NOthing to see there... I hope I gave you a discount if that's the board you got. hehe. They don't hurt anything. However, like Oprah, they serve no purpose and have no intrinsic value.
I think I figured out what happened with one of the 1000amp controllers. It had a very unusual failure that I hadn't seen before. There was a hunk of M- and a hunk of B- bus bars that had vaporized right at the same spot. I believe that for whatever reason, an arc was started from B- to M- right at that point. It may have had nothing to do with a mosfet failing. Hmm... Maybe there was a bit of metal inside the controller that bounced around and bridged B- to M- right there and got the arc started. I'm not sure though.