Ultrav23, are you saying that the One-For-All remote contains discrete commands that are not already in the Harmony database?
Note 1: If the original OEM remote has discrete commands (or any other missing commands), then you can teach them directly to the Harmony remote.
Note 2: Sure the discrete method is more robust, but the device must support discrete commands. The Harmony database may contains discrete commands for a brand but not all models (for that brand) support discrete commands. That is why one should try all the commands in device mode to see if this particular model supports any of the available discrete commands.