One thing I've learned with Infinity over the years is you need to know what your opponent can do with his units, what they are good at, and what they aren't that good at. One reason I always suggest you should take a look at opposing faction units in the army builder. Look up their skills, equipment, and take note of their load outs. One thing I find with newer players and even vets is they can be caught off guard by a unit they've never seen put on the table before. This isn't the end of the game but one doesn't need to be caught off guard like that.
Now do you need to know all the other forces in the game like your own? Nope. It sure does help though. When I first started out one of the most common forces I would play against was the Nomads. My first couple of games I learned from experience who could what and how. It usually didn't end well for me. Eventually I started to look over the Nomad units. Taking note of load outs, how much things cost, and starting to see how a Nomad force could be built. After that it was coming to understand how my opponent preferred to play his Nomads. I wasn't caught off guard after I started to bring my knowledge and I even started to get good at locating LTs in my opponents forces (he's a big fan of Interventor and Custodier LTs).
Whenever I had the free time I would bring up the army builder and browse the other factions. Hop on the official forums and go to the faction sections. Those areas a chock full of knowledge about how a faction could use a unit or even specific tactics and strategies.
One must keep his opponent in mind though. One person can use a unit differently then someone else. This is where straight up playing experience comes in. To give you an example of this I recently started playing against an SP force. I've always struggled against SP since they were introduced. The combo of their ODD, CQB prowess, and link teams have always given me fits. I've never found a great way to combat that until recently (4 games against them later). I'll run it down for you.
SP want to get close to you. The weapons the majority of the units in SP have are for close to medium engagements. SP are designed to get close to you thanks to a judicious amount of ODD and smoke/eclipse grenades. Most SP players will have a firebase unit to provide over watch but not all the time.
You can start to use their common tactics against them. I found that mid-field units armed with mines or that have minelayer are a great way to dictate the path you want SP link teams to go or even box them in. This is common board control tactics.
With that in mind you can start to funnel SP into engagements that favor you thanks to long range bands. This is what I call keeping them at arms length. As noted SPs main range bands are close to medium. They have some long range weapons and we'll get to that in a moment. You can start to outrange their teams and start to pick off members from teams. It's even better if your long range weapons are impact template capable.
Before you can keep them at arms length though one must take out their long ranged unit. This usually comes in the form of Phoenix, Teucer, Atalanta, Agema, or a Feuerbach/HMG Thorakitai. These units can take out your long range threats and let the other forces of SP get into their optimal range bands. Best to keep that from happening.
It isn't the end though if SP get to the locations they want to. You must be prepared to counter-attack those positions. I'll tell you right now a counter-attack is going to involve casualties on your side especially when taking on a link team and especially a Myrmidon team in SP. My favorite counter-attack units are my template throw away units (Monks and Kuang Shi). The templates because they don't care about ODD and cover. Throw away because you want to make this attack an unfair trade for the SP player. The counter-attack unit will most defiantly fall but as long as he takes out around 2-4 of the team he's done his job. Other counter-attack methods I can suggest are mines. As long as you mine laying unit can do it without getting shot to bits dropping a mine around a corner which has LoF to a unit on the other corner is always great. It's part board control part counter-attack.
So in all if you can pin or bog down, keep at arms length, eliminate their overwatch, you'll find yourself in control over an SP in your game.
I think that's fine example of showing off ones knowledge of an opposing force. As for my opponent he runs SP with their usual fash smashers and an overwatch/long range threat. I kept those things in mind and planned accordingly.
