I seriously doubt a fancy ramp design gives any significant performance increase over a simple up/down stair shaft. I don't think any science has been done on this in 0.34.x at all.
I have always just used up/down stairs so can't vouch either way, but here's a thread that at least has a bunch of anecdotal evidence. I'm in the process of slowly replacing stairs with ramps in my fort to see if I notice any effect...
That thread was from just before the release of 0.34. I don't really think there are huge changes in the core pathfinding code, but there might be some auxiliary changes that could be significant. Consolidated hauling (get bin, go to workshop, put 8 items in bin, vs. 8 dwarves each taking 1 item from workshop) is the one that springs to mind first.
I look forward to seeing your results, though.
Well, don't hold your breath
; once I figure out some good ramp designs I plan to replace all the stairs in a single sweep, if possible, and note any differences, but this is in an active fort, so there is so much outside influence the results won't be very objective...
If I had more time I could spend on DF I'd totally want to make a "test fort" solelyfor this kinda thing, but it's hard enough to find time just to get attacked by goblins and zombies as it is
EDIT:Apologies, I forgot that it was disabled. Haven't played lately and my fortresses almost never make it to where the economy would kick in. And I saw options for turning it off in init when I set up my new version so I guess I just sorta assumed... *shrugs*
EDIT2, THIS TIME IT'S PERSONAL RELEVANT:Is enemy zombies dwarves stuffing up all my coffins a bug, or working as intended?