What accounts for the variance in confirmed transactions. I have see anywhere from 100 percent to zero. Is there a remedy in the works for this with the new IRI or is it just a function of a young tangle and the only solution is more users?
Some reasons that come to my mind (there are surely others):
When the coordinator is off/broken, the confirmation rate is zero
When conflicting transactions are posted (either intentionally or by reattaching a single transaction multiple times in short time intervals), only one of them can get confirmed (which also harms the legitimate transactions who chose them as a tip), which will reduce confirmation rate
Transactions that are attached to very old transactions, or extreme bursts of many transactions within a few milliseconds (maybe caused by full nodes that have too little bandwidth to stay in sync properly) will result in a "broad" tangle with many tips. It will take some time for these broad tangles to converge (reduce the number of tips to a reasonable amount) and since the Coordinator will only choose two tips every minute to confirm them, confirmation rate will be low at that times. In fact, when such a situation converges later (as the network connectivity problem is resolved), I have already seen confirmation rates larger than 100% (i. e. more transactions got confirmed last minute than were introduced into the network).