Monty? Do you have a problem or just a general question? ...... seems like you're talking to yourself outloud while thinking and looking at the furnace.
The high speed is "usually" reserved for air conditioning mode and would be energized by the G terminal on the thermostat connection terminals at the furnace.
If you don't have air conditioning you probably only have two wires at these connections..... "usually" red and white and they would be connected to R and W terminals.
A connection between R and G terminals is what powers the fan's high speed and does it safely as to not power both speeds at the same time......... something that is VERY bad to do.