The XT was advertised as having tools for the off-road user - and the photos seems to suggest that is what it was for. So much so that I didn't even bother looking at one when they first came out.
The answer to your question is a resounding "No". It is primarily a road navigation device, with some tools that I would call 'iffy'. But it came with maps that were designed for off road use - but here in the UK, there aren't so many of those around. Mostly road traffic isn't allowed on off-road tracks. The only ones that are, are labelled as BOATs - Byways Open to All Traffic. These are relatively few and far between. There are also unclassified public roads which are sometimes less used and have the appearance of tracks.
But I like it (mostly), and I have a 595 which I thought that I would prefer, but its the XT that gets put onto the bike. I think I have tamed it now !
The Explore software allows the rider to use satellite images and to plot straight lines over the top of visible trails, and then display them in full photographic 3-D imagery with the line superimposed. Something like this.
It also has tools that will allow you to follow such a track with navigable instructions, and or to use the back packers technique of walking on a fixed bearing for a fixed distance before getting another fix. All the time the XT will show where you are and where the plotted straight line is - the logic being that the rider / walker will have to negotiate boulders, muddy patches. This turns out to be a rather relaxing way of navigating on the road. Like having a paper map witht he screen keeping its finger on your current position and a line indicating which general direction to head in to get back to where you itended.
But I don't use Explore. Although I've looked into it in a lot of detail, and tried everything that it has to offer, there is nothing in there that I wasnt to use. I continue to use Basecamp for route planning, and an Explore free Zumo.
But it also has an excellent array of tools for the road user. It is fast and although it has an annoying preferecne to head for the nearest main road, that is easily anticipated and managed. It is a good bit of kit for the road rider.
Except for one rather significant glitch. Out of the box, it doesn't like you to head away from the plotted route, and does everything it can to take you back to it if you need to deviate. But between us, we have identified when this happens, come up with a couple of ways of preventing this behaviour and it behaves perfectly on routes that have been modified in this way. The fix is a two minute job either at your computer, or when on tour with the Zumo in your hand.
It is nice to have a unit with a decent battery life, a bright screen and onboard speakers for use when it is in you hand at home. I have counted 6 different ways in which you can use the XT for navigating on road.
Fill your boots -
Link here