As someone else who runs without the line (and ABS, but that's due a knackered finger more than anything) I agree that it does lead to consistency. To be honest, the main reason I use it is because I do tend to jump around quite a bit and the line provides a useful reference point if you go (as I have many nights recently) from R3 to B Class in one go. That reminder that you need to apply the brakes a bit earlier than you were doing in your previous run has saved many people from having an Anteater smashing into the back of them

One of the things I'm aiming to do come FM3 is to turn off the line. To be honest, apart from the adaption between classes (which I think is learnable), the main thing keeping it on for me is that the random car thing is basically a big comparison. Switching off one of the parameters part way through would rather wreck that, hence the wait until FM3. ABS though will stay on until when/if I get a wheel.
Even then, I suspect that there wouldn't have been the carnage in the first race that there was if we'd been prepared (and full credit to everyone for sticking with it even if they were damaged). Certainly by the end of the 10 lap race I was back to hitting my marks, even if I was a bit more nervous at that last corner. So, if you choose to run the next championship with the line turned off I'll have no complaints.
(Re-reading that last paragraph it reads like I'm having a go - I'm not, just saying that one of the lessons to learn is that if there are any settings for a championship it would be better if they were announced pre-season).
Regarding the MVS enduro, I would say that that track, Suzuka East and Road Atlanta Short are probably the easiest lines to switch off the line due to the sheer inaccuracy in most places. You just have to remember in the first corner to look for track-side markers rather than a big red triangle
