toltec wrote:
1. To avoid prosecution, I can usually keep my speed legal without reference to the speedo, however there is still a risk I will go 1-2mph over and it is one I do not care to take.
In the five boroughs of NY, one can safely do 10 to 12 MpH over the posted speed 'limit' without fear of being pulled over. I haven't needed to check in a while, since I seldom drive through traps during traffic conditions which could physically permit extralegal speeds.
Quote:
2. Fuel economy, it is easy to allow your speed to creep up on a motorway, for example, if I have to accelerate to make a clean pass a speedo check is useful when dropping back to cruise.
Had I cruise control AND a fuel consumption readout, the speedometer might become redundant after a while. Few, if any vehicles improve their highway MpG above 60 to 65 MpH, so I just keep it between 60 & 65MpH on the highway.
Quote:
3. If I know what speed I am doing and how far to a destination or junction I know roughly how long it should take.
A satnav would suffice here.
Quote:
4. Checked as part of a general instrument scan, fuel, temp, warning lights, time, etc. or if using a sat-nav distance to next turn.
In this case, I hardly notice the number anymore.
Quote:
5. When leaving a motorway, especially when dropping to urban rather than NSL roads, it can sometimes take a minute to drop my speed perception back down so using a speedo helps me make the shift quickly.
I still do this every now and again. I've found it helpful, but almost never necessary.
Generally, the speedometer is only necessary because someone else cares about the number.
However, in inclement weather, I find myself looking at it if my 'g-meter' gets nervous before the entry of a turn, then I'll check to make sure I'm entering the turn at a speed no greater than 10MpH over the posted curve advisory speed.