#1 -- Building guerillas is not a waste of time and resources.
After fighting the AI governors who kept trying to build guerillas in my cities,I gave in and let it. I found something quite surprising. That little defensive bombardment of a guerilla kept my infantry in the stack alive a lot longer. When I kept a 3:1 infantry to gureilla ratio in my stack (or 2:1 if the stack is smaller), I suffered significantly less casualties. The infantry would be damaged, but that defensive bombardment from the guerillas would be enough to keep the infantry from death. This also led to more battlefield promotions to elite units. The same goes for keeping one or two guerillas in your border cities. Before someone argues artillery does the same thing, keep in mind artillery cannot be airlifted.
#2 -- Why expose a landing force to enemy counterattack in the first place?
In conquests, once you are in the late industrial era, there is no reason why you should land an assault force in the open only to wait a turn for a counter attack by the AI. Marines have an attack value of 12, and with some sea bombardment and some air bombardment, sufficient numbers of marines can take any city. (Hopefully after you destroy the civil defense...) This works even against MechInf. My rule of thumb is a transport full of marines per MechInf in a city. This is usually more than enough, but it never hurts
Ideally you can capture a city with an airport, and can airlift the reserves in. If not, you have transports standing by with your heavy defenders and artillery. Defending a city (size 7-12) means you get that city defensive bonus, plus you can dig in. If you have enough troops in your transports, you can even launch an attack from the captured city on the same turn!
#3 -- Destroyers are great lookouts, but the key to sinking an invasion fleet is the submarine
The AI has this uncanny habit of leaving your lookout ships alone and keeping all its escort ships with the transport. Now this makes no sense to me, and here's why: Escorts in the same stack as the transports only protect the transport from surface ships, leaving the transport vunerable to submarine attack! If the AI knew how to deal with submarines, it would send out destroyers ahead of the stack containing the transports, and would seek out and destroy any submarines it may find. To defend against an invasion fleet, all the human player has to do is place destroyers at strategic locations to spot the incoming ships. Once spotted, submarines stationed at strategic ports in the homeland can swoop in and sink the transports. If you aren't playing a seafaring civ, the alternative is to leave a submarine underneath your lookout destroyer.
Veteran submarine vs veteran or regular submarine results in the submarine almost always winning (anectodally, I think I have lost 1 or 2 submarines total in all the games I have played). What's even more interesting is that once the transport is sunk, the escorts all go home! Instead of using its ships to meanace your coast, the escort ships simply turn tail and run!
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Anyone else have some unconventional ideas? Mine might just be run of the mill stuff...but it's late and stuff heh
After fighting the AI governors who kept trying to build guerillas in my cities,I gave in and let it. I found something quite surprising. That little defensive bombardment of a guerilla kept my infantry in the stack alive a lot longer. When I kept a 3:1 infantry to gureilla ratio in my stack (or 2:1 if the stack is smaller), I suffered significantly less casualties. The infantry would be damaged, but that defensive bombardment from the guerillas would be enough to keep the infantry from death. This also led to more battlefield promotions to elite units. The same goes for keeping one or two guerillas in your border cities. Before someone argues artillery does the same thing, keep in mind artillery cannot be airlifted.
#2 -- Why expose a landing force to enemy counterattack in the first place?
In conquests, once you are in the late industrial era, there is no reason why you should land an assault force in the open only to wait a turn for a counter attack by the AI. Marines have an attack value of 12, and with some sea bombardment and some air bombardment, sufficient numbers of marines can take any city. (Hopefully after you destroy the civil defense...) This works even against MechInf. My rule of thumb is a transport full of marines per MechInf in a city. This is usually more than enough, but it never hurts

#3 -- Destroyers are great lookouts, but the key to sinking an invasion fleet is the submarine
The AI has this uncanny habit of leaving your lookout ships alone and keeping all its escort ships with the transport. Now this makes no sense to me, and here's why: Escorts in the same stack as the transports only protect the transport from surface ships, leaving the transport vunerable to submarine attack! If the AI knew how to deal with submarines, it would send out destroyers ahead of the stack containing the transports, and would seek out and destroy any submarines it may find. To defend against an invasion fleet, all the human player has to do is place destroyers at strategic locations to spot the incoming ships. Once spotted, submarines stationed at strategic ports in the homeland can swoop in and sink the transports. If you aren't playing a seafaring civ, the alternative is to leave a submarine underneath your lookout destroyer.
Veteran submarine vs veteran or regular submarine results in the submarine almost always winning (anectodally, I think I have lost 1 or 2 submarines total in all the games I have played). What's even more interesting is that once the transport is sunk, the escorts all go home! Instead of using its ships to meanace your coast, the escort ships simply turn tail and run!
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Anyone else have some unconventional ideas? Mine might just be run of the mill stuff...but it's late and stuff heh