I've been looking through the notes and tests that I carried out when I was trying to understand its behaviour, and they are not complete - partly because I got lured by the possibility of trading it in for a 590, before I finished the tests !
At the time, Basecamp was the product to use for producing maps on the 660 - we were constantly told by Garmin to use Basecamp. Basecamp (to me) was rather an unruly beast at the time, and frequently died on me. But then it went through some upgrades. It is now upgraded beyond the capabilities of the 660, so Mapsource is once again the tool to use. If BC is used, the navigation 'may' behave very oddly.
I know that the 660 recognises the BC Via and Shaping points - but any point can be 'ignored' if you rejoin the mageanta line (just like shaping poinnts in the 590 and later zumos). Shaping points do not announce, Via Points do.
Yet Mapsource has no facility to specify via/shaping or alerting/not-alerting. From my test notes, the behaviour seems to depend on where the points fall when you place them. If there is no named feature where the point is dropped, it is a shaping point and appears as a small square in the trip list - and will not announce. If it has a name, it becomes a Via point and appears as a green disc in the trip list - and will announce. Larger towns have larger discs. The same is true in the later Zumos - but you can change them. The 660 refers to both kinds of points as Vias.
But I could really use a couple of pieces of information - if anyone can provide any detail please.
- A screen shot of a route on the 660 showing any mid-route points. I cannot remember how they appeared on the screen - if at all.
- If using Basecamp to create a route, is it better for the 660 to use all Via Points ?
- Can tracks be displayed at the same time as maps on the Zumo 660 screen ?