Romanis responded by developing a suite of TTL models that reposition assessment as the engine of learning, not just the final report card.

This live data feed is the hallmark of the TTL model.

This is where Romanis diverges from previous theorists. Modification requires technology to meaningfully redesign the learning task.

For a 7400 NAND gate, Romanis’ equivalent circuit shows two input diodes (emitters) feeding a common base resistor. This allows a student to calculate: