Just wanted to chime in here with my first post on these forums on which I've been sucking up information for the last month and a half of getting into Civ V. Thanks for the great strategy snarzberry. You helped me to my first Deity win.
I started a standard Pangea Deity game (8 Civs 16 CS). I managed to bulb Chivalry on turn 84 with 2 cities. I had my Chariot Archers ready to upgrade with enough gold to do so. Cathy was to my north and had expanded close to my 2 cities. She DoWed me and I started the assault around turn 88. Unfortunately I had not built a barracks in my capital so my Keshiks were a bit slow on the upgrade path. Also, I was not fully prepared as I advanced in the rough terrain for the shear number of units that Cathy would continuously spam at my force. It was a bit of a slog to get Yaroslavl, but after I did and slowly pushed to Moscow some of my guys were upgraded to logistics and the going got easier. She offered me peace and St. Petersburg so I grabbed that, continued to expand my army and then went after a weak Persia with nice Wonders to my east. Took his cap, and 2 other cities and made peace with him.
Then I finished Cathy leaving her one city and went after Alex who had filled the eastern portion of the continent (and blocked expansion from France and Egypt who spawned on a Cape Cod shaped narrow growth off the south eastern edge of the continent). Alex had a big army and a tech lead but highly promoted Keshik's tore him up, I just needed to be careful of his CCs that did surprise me and cost me a couple of Keshiks. Thus in my first 100 turns (by around turn 179) I had stopped one runaway and taken 3 capitals. I was in a winning position at this point and could have pursued any victory, but wanted to go for a Domination win. During this time I was about 8% behind in tech from the leaders (Alex initially and then Askia).
To my west (behind a wall of mountains accessible through only 3 passes one of which was blocked by Cathy's remaining city) were Askia and the Ottomans. By the time I finished Alex, Askia had crushed the Ottomans and had an army about 3.5 times the size of mine according to the Demographics page). Given the difficulty of accessing this area and Askia's vast army, I kept signing RAs (without the benefit of Rationalism or the PT (built by Egypt)) and built out my infrastructure for science and production. My keshiks had been killing Alex's riflemen at the end, so this seemed a safe and wise course given I had not beaten Deity yet. With artillery in place and a slowly building force of tanks and infantry (with 8-10 super promoted Keshiks for backup) I Dowed Askia on turn 222 and let him beat his head against my defenses for a bit. Once I had fighters built to protect me from his, I began to push west and quickly teched for nukes and lasers and finally ate up the entire western half of the landmass by turn 260 or so.
By that time I had 10 logistics/Air repair promoted Stealth bombers and overwhelming military power so i moved my troops to the peninsula and hacked down the French and the Egyptians for a turn 280 win.
After failing miserably attempting to emulate Wainy's bowman rush with Babylon on deity, I found this much more suited to my style of play. It doesn't hurt, of course, that Keshik's are the most OP unit in the game.
I definitely could have performed better with more Deity experience, especially in terms of going more forcefully for HS/PT/ND while prosecuting my initial slow "blitz", but I had great fun with this. Just wanted to post here to say thanks and to encourage other Emperor/Immortal players that have gotten frustrated with Deity to give this a whirl with Mongolia or Songhai.