It depends on the ECU if it is going to help anything with warmup smoothness. But if you do engine off coasting the 1 wire sensors cool down quick and take a few minutes to warm back up even if the engine is at full temp while driving easy. I would suggest using a 4 wire sensor and running the ground back to the ecu to get a lot more accurate signal. On an OBD1 Metro as soon as the water is over 110 degrees I think, and the sensor is reading the car then starts using it.
4 Wire Oxygen Sensor–MetroXFi.com
lot more info on switching to a 4 wire sensor there.