The other is being able to rapidly hook up resources if you happen to start with an appropriate tech as the other one.
Indeed.
I don't know how useful that would be in this particular situation.
I feel free to give the spoiler now, given that it's no longer a possibility for Sis' game. Settling in place on turn 0 and moving the warrior to the hut provided free Fishing, negating the need to hook up the pigs, corn, or the third resource 2W that has yet to be uncovered.
My reasoning was it is uncommon to not get more than 1 resource in the bfc so I have a good chance at another and I don't care for the early wonders, second culture expansion is enough for Pyramids.
We can even compose a list of which resources might be on the riverside plains tile. I think there's a strong chance that it's iron or horses, given the new BTS algorithm to reduce/eliminate copper in the BFC. I world-builder tested some possible non-strategic resources under the fog (the tile is partially revealed), but none were at all visible without fully exploring the tile.
The Pyramids can definatly wait for the second border expansion. Early Writing for an early Madrassa in the capital can help expedite this. We'll want early Writing for an early Madrassa anyway; this start is food rich and relatively production poor, so I think we'll be running specialists very early. Additionally, delaying the Pyramids for the second border pop leaves (some) time to research either Mathematics or Monotheism (and hopefully land a religion), to help further boost the chops.
Monotheism would allow for bulbing Theology should a Great Prophet pop (we can run three specialists here at pop8, which we can easily reach through religion and Representation, while still maintaining significant production). Whether Sis wants to bulb Theology, settle the Great Prophet, or build a shrine is his choice. Bulbing almost seems to be the weakest, but Theology could make for some good trading.
If Sis would care to confirm that the third resource is indeed a strategic resource, he can move the settler 1N (to the proposed stone site) on this turn, then move the warrior 1SE on the next turn. This will reveal the third resource's tile, and still leaves Sis the freedom to move the settler back to the starting position to settle there, a move I would definatly make should that third resource be strategic.
I just ran some numbers real quick, and came to the conclusion that settling in the starting position is the best option. If that is indeed a strategic resource, then there is a huge long-term advantage for returning to the starting position and settling there.
Working five tiles, he's looking at either +6F/13H/6C or +6F/12H/7C by returning to the starting position, depending on what strategic resource that is (first numbers are copper and iron, second is horses). It has 17 riverside tiles, three hills, and 17 forests in the BFC.
Working the same number of tiles at the stone site produces +6F/12H/3C. It has 14 riverside tiles, two hills, and 12 forests in the BFC. It does, however, trade a number of plains tiles for grasslands, a trade I'm not necessarily a fan of.
Looking at settling in the starting site, there are six riverside grassland tiles that can and should be chopped for the Pyramids. Additionally, there are three hills to chop early on for expansion (or the Great Wall, I guess). This leaves quite a few plains forests to preserve for the health bonus, lumbermills, and eventually forest preserves.
One of obsolete's methods of pursuing his wonderspam is to settle in place (probably so as to avoid 100% wasted turns), scout for the stone or marble, and settle his second city on top of it, perhaps pre-chopping the forests while waiting to connect this new city.
Picking up the Great Wall is a nice idea for a Protective-based provocative war strategy. However, I don't see that as being a strategy that will carry you forward into Immortal. It's more of a role-playing strategy that works on low/mid level difficulty settings. While that's all well and good for MadScientist and his games, I don't see that being the focus of the ALCs. From what I remember of their start, ALCs are about progressing through difficulty settings, and the techniques for doing so, not exploring interesting (if detrimental) variants.
Those are just my 2

. Sis will do what he feels is right, and rightly so. As I said, he can reveal what the third resource is without deviating from settling the stone site. Settler 1N on this turn, then warrior 1SE on the next turn. If there's "nothing" there, I would definatly return to the starting position to settle "in place," but he can also settle the stone at this point.