The reason for a heat exchanger is consistent transmission operating temperature, therefore consistent performance by maintainig tolerances. Quicker warmup is also a result, as the transmission will generate very little heat by itself until the vehicle is in motion. I agree an independent system can work well, but should be regulated somehow to maintain a consistent and adequate (high enough) temp. I can say from monitoring trans fluid temps in drag racing applications, that too cold DOES hurt performance. I don't believe the heat exchanger design is strictly a financial one. My opinion, and it is just that, an opinion: The heat exchanger design works well and should be monitored and additional cooling should be added IF NEEDED. But, we can all agree that TOO MUCH heat is the enemy.
79 International Wayne