After building transmissions for a while, there will always be an overdrive regardless of what the final drive is. If you went stupid and put in a 6.11:1 final drive, would that make 2nd gear an overdrive? No. A transmission has what a transmission has regardless of your final drive in the world I was used to dealing with. All of a sudden, a 4L60E wouldn't "lose" an overdriven planitary because of a gear swap, it still maintains the ratio internally as the transmission doesn't care about anything past the output shaft. It is still in reducing or multiplying the power/rpms transmitted from the input shaft to the output shaft.

Even though you don't say that there is a numerical overdrive, there still is when you look at the sheer ratios.