I've used and tested this strat a lot on immortal the last few months. One quesion and a few remarks:
Q: beelining to Rifling do you make the detour to Economics for the free merchant? I'm not sure, i've tried both, the free GM is great for updating troops but the 5 turns it genreally costs to research can just make the difference in being in time or too late in attacking. Ultimately it depends on how close your victim is to Rifling or military science i guess.
Some remarks,
Blocking the AI's is a great strat, it's not always as easy as it is in the example game given here though, sometimes you have to block in 2 or even 3 directions or you have no backyard (coastal or worthless tundra behind you). Not such a problem, if you can get 6 reasonably good cities up that's good enough and generally better (for this strat anyway) than going out of your way to settle cities very far from home which will hurt your early research too much to fully profit from this strat. I'd have to test it but i don't see why it wouldn't work with 4 cities even, if you get the globe up in time you can rely heavily on drafting, i guess these 4 cities have to be developed to the max in this case though to get enough science in (but also a super science capital may do). At least you can have the slider close to 90% in this case.
On immortal if i really try hard and focus on getting the globe build in time (begin with theaters and the globe asap, researching or trading for drama before lib) i can get Rifling between 1100 and 1300 and so be ready to attack between 1200 and 1400 which generally is good enough especially if you get the globe done before rifling, just draft muskets in this case.
On building the globe for this strat, plan ahead you'll basically want a site with
2 food resources but also some production (or forests) so you can get the thing build in time. this can make a difference as to how you settle this city, i find myself forgetting about this time and again, finding myself with no suitable city or finding that i have a good city but there are three cottages where there should have been 3 farms. To optimalize this you should be planning in the 1000 BC-1AD stages i feel. The more units you can draft (especially if research is ok and you can reach rifling in good time so you can afford early nationhood) the better your position will be.
It's not always good enough though, there are times when the chosen victim will be close to rifling when you're ready to attack, rifles against rifles is a total no go so what can be done in this case....
The afore mentioned scenario most often happens when you're on a Pangea where all the civs know each other, in this case overall research is fast and
techs like printing press and replaceable parts are generously traded amongst the other civs.
In this case (granted you see the aforementioned problem with the rifling strat in time) i think it's possible to go another route. As you can generally see how far all the civs are you can delay liberalism research and bulb it till there's one turn left,take it off the research queue then go about bulbing printing press, researching gunpowder while trading for engineering (remember research is high in the scenario i'm sketching here). Then bulb chemistry and take steel of liberalism. I've tested this in one immortal game (where AI research was slow though) and it worked like a charm. If not in time to get steel from lib, no problem, just research it, bulbing chemistry and researching steel is still faster than having to research replaceable parts and rifling. So you can have cannons really early.
There're a few issues with this,
- Most important your stacks with lots of cannons (and drafted muskets) in it instead of rifles will not be immune to counter attacks from mounted units, be sure to build some pikes to protect from cuirassiers and knights, muskets are not strong enough and mounted units will attack these sort of stacks, with pikes in it they won't attack (or lose expensive mounted units against your not so expensive pikes).
-You don't need spies as you'll have enough cannons to bring down defenses fast, this saves you from the need to sacrifice research on spy points. Basically you tear down defenses but also attack with superior cannons(upgrade to cityraider not barrage) which have a good chance to win
once defenses are down, you ultimately take the cities with the drafted muskets and whatever you brought along (maces, pikes).
-Once you get to steel it pays to research Military science and build some backup grens especially if the victim is indeed close to rifling they'll come in handy. Begin the attack asap though upgrading prebuild trebs to cannons and moving in together with drafted muskets. At the moment the enemy does get to rifles you'll probably really need the grens(there's one thing i'm not really sure about, if the enemy gets rifles will it attack your stack? Could well be that since the AI regards a rifle as a defensive unit that they'll leave you alone, still you'll need grens in this case or you'll lose to much cannons)
Summarizing, the rifles strat is faster, you don't have to build pikes and you'll break defences with spies, moving on with the superior rifles. the window of opportunity is kind of narrow though, once the victim has researched rifling or military science (grens) the fun is over.
Cannon strat takes longer, since the cannons not only have to bombard but also attack they'll need healing. Just as in warlords the opportunity window for this kind of attack is alot bigger though, basically the enemy is defenseless
unless the've got steel themselves but somehow it takes the AIs a long time to research to steel.
The only difference with Snaaty's initial strat is the beeline to steel, there are no changes otherwise, you'll try to get to steel asap instead of rifling but building globe ,drafting and preparing otherwise (more pikes for this strat) is still essential.
This was a long post, since i've only tested it once not all the ideas have fully cristallized so discussion is welcome.