[Goat Blower]

It's adding a dowel pin machined into the cap and the block that the main studs go through. It provides tighter clearances to supposedly keep the caps from moving at all.

I've been a little leary of the unsupported caps on the 2.4 as well. But I have no intentions of spinning mine past 8200 rpm, whereas Kiggly on NABR is spinning well past 10K on a 2.0. The 2G's also have a windage tray that bolts up along with the girdle. I had one to put on my 2.4, but it would have been easier to just make my own, and just got scrapped when time got short.

In short, yes, girdles are good. But most will probably never really need them.