RE: The Guessometer
The main reason I don't use it is because my brain really doesn't work based on distance left, and nor does my mileage today depend on how I was driving yesterday! I usually don't know where I am mid-journey, what good is a range estimation?
So instead if, for example, I know I have an 80 mile journey I need to make sure I am doing not less than 10 miles for each octal on the SOC. After a half hour, I have no clue how much further I need to go but all I do is note the mileage shown every time the needle gets to the next octal mark.
The range estimate could be miles out in either direction, and becomes a function of how I was driving yesterday, not today. Fat lot of good that is!!
If I only have 60 miles to do, all I do is make sure I am getting at least 8 miles per octal.
On my best-ever 122 mile trip I noted that I was getting 15 miles between octals. Not a common sight....