To calculate the efficiency of instruction with TIC, multiply the probability of learning with the choice of instruction made for Dimension 1 by the probability of learning with the choice of instruction made for Dimension 2.
The more efficiency the instruction, the lower the likelihood a learner will fail to meet criterion for a lesson.
Efficient instruction follows the shortest path through these choices, so that learners meet the criterion for a lesson.
The most efficient instruction reduces the number of trials-and-errors of learners to meet the learning criterion of each lesson. These ways are consistent with descriptions of behavior patterns people use to learn.