So in theory I could create a new armory wallet. Make one transaction with it, then make a copy of the wallet file. Continue to use the wallet making hundreds of transactions. Then take that copy I made a while ago, import into Armory and I would see all that happened with that wallet?
You don't even need to do a transaction.
When Armory creates a new wallet it generates two numbers: a root key and a chain code. Every address that wallet will ever use is an output of a function that takes those two numbers and a sequence index (1,2,3,4...) as inputs. You could backup that address once, before ever having made a transaction, then import it to another copy of Armory after having made a few trillion transactions and Armory will be able to calculate your balance from that original backup file.