For the XT, what is the result if you have the adventurous setting at a minimum, so assuming that you have the "fastest" option it should give you the least time? This I think is where you see the strangest results as the resulting route, as per JB's example is nowhere near what is logically the "fastest" route.
I have played around in my XT, using the Chelmsford to Norwich route, simply by way of reference.
By default I have my device set to: Faster time, promoted recalculation, avoid U-turns, avoid unpaved roads.
To create the base route of Chelmsford to Norwich, I used the method shown in er-minio’s excellent tutorial:
This gave me a pretty direct route, up the A12 to Ipswich. Around the Ipswich ring road, then up the A140 to Norwich. In all, 80 miles in 1 hour 48 minutes. In short, what I’d expect.
I then touched the spanner in the top left corner and selected Route Preference. This brought up choices of routing for the route:
Faster time (this one was already selected as it’s my default setting)
Adventurous
Straight line
Shorter distance
I chose Shorter distance. This made no great difference at 80 miles in 1 hour 53 minutes. Not surprisingly, it is just about the same, simply as it’s basically just two roads between Chelmsford and Norwich.
I then touched the spanner again, then Route Preference again, then Adventurous. This brought up a route of 80 miles in 1 hour 48 minutes. In other words no different to the faster time route. But…..
I then touched the orange box in the upper right corner, next to Go! The device made a recalculation, producing a very different route of 106 miles in 3 hours 7 minutes. Have in mind that the standard ‘fastest route’ that the device offered up was 80 miles in 1 hour 48 minutes. The route is now 26 miles longer by distance but some 1 hour 19 minutes longer by time. That is a significant difference. The route now goes: Chelmsford > Great Dunmow > Saffron Walden > Haverhill > Bury St Edmunds > Diss > Norwich. It really isn’t too bad, going nowhere even close to Ipswich.
I then slid the slider control from maximum, one unit to the left. This made no difference.
I then slid it one more unit to the left. This altered the route a bit, giving 88 miles in 2 hours 24 minutes.
I then slid it again, right to the left. This gave 80 miles in 1 hour 47, with a route shape pretty much like the shorter distance option.
Conclusion / comment
A. Depending on the A to B journey, fastest route versus shorter distance, might make little to no difference. A paper map may well tell you why.
B. Adventure routing of the same A to B route, can make a significant difference. But, it might well depend on what roads are available for the device’s algorithm to chose from. On the Chelmsford to Norwich route, there are plenty of roads to the west of Chelmsford for the algorithm to work with. On a short A to B route, this potential may well reduce, obviously.
C. All the calculations and recalculations were quick and undoable.
D. Are the ‘Advenure’ routes any good? Arguably yes:
1. If you have the slider set to maximum and there are enough roads available for the device’s algorithm to work with.
2. Are they perfect? To a degree that might depend on how fussy you are. Some might make a silly detour, just to go around a roundabout. For what it’s worth, Kurviger can be very guilty of this, too.
3. If you expect the algorithm to take in every really small road between A and B, you might well be disappointed. But, if that is your expectation, then you’d be better off making yourself a bespoke route, rather than letting a dumb (but really quite clever) device do it for you. Or, learn how to alter routes from within the device itself, which really isn’t too onerous.
4. If you think your pre-XT Garmin device was better at it, then use that and pat yourself on the back.
My suggestion:
1. Try it for yourself. It’s free and you can’t break anything.
2. Maybe start with my Chelmsford to Norwich route and copy what I did, to see if your results are the same.
3. Try your own trial route.
4. Don’t moan…. The device can’t hear you.
PS My use of the words ‘you’ and ‘your’ is generic. It is not directed to you, John…. Or anyone else
& 8 mins quicker to boot)
