Question regarding building changes in 3.0

The new expertise perk will allow us to gain 25% building stability. I assume this means instead of spanning 8 ceiling pieces between two foundations, we will be able to span 10 ceiling pieces between two foundations. Can you verify this? Sounds like an amazing change, would like to know ahead of time if that is the intent, or if it’ll end up being 9 instead.

Another question.

The new wall pieces that are two pieces in height…
Do they provide a noticeable benefit to FPS or server load? Would it benefit a player or clan to deliberately use many of these pieces on a large build to improve performance? Or no significant change and not worth considering?

In theory it should due to the fact you use less pieces (objects) in a game that needs to load. Also the rooms wouldnt be as constricted with new walls. The only con I can think of it would be easier to avoid thralls from poking you due to height.