Performance difference between 2T vs, 1T on 680i

I was just looking at this thread on XS and it kinda surprised me.
With the subtimings roughly the same and the other difference being RAS Precharge(which barely changes thing), the margin between those two timings seems to be ~130Mhz!
That's way larger than I anticipated.

(Self note: For Bungholiomarks Only)

Kentsfield+680i

Doesn't work well with 10-11 multiplier, generally limited to around 310Mhz FSB regardless of environment.
Looks like 6-8 is alright.

High tRFC of 66 is good or just use Auto(in ASUS?) compared to 35-42 in 965P.
And 100+ isn't bad either if manual setting is stable.

1:1 and 5:6 are strong dividers, use those to get scale high