Righty ho. Long straights using easement curves the Bob way...
I've done a quick test which was just a short straight followed by a random curve. Then I flew away for a random distance (which turned out to be 10 miles

) and stuck a chimney down along with another stretch of track so I can find it again in the map view.
StartPlan.jpg
At this stage I know that my chimney is roughly in the direction of the blue line. I've stuck an arrow on the most valuable aspect of this excercise, which is the length of the curved track
before the lead-out easement into the straight.
All that matters is getting the length of this curved section correct.
StartGuess.jpg
This is where I ended up after my first try. The length of the curve ended up being 291.6m, as you can see.
Attempt1.jpg
I always try to have the original curve longer than it needs to be, because in the early stages of this process it's easier to chop bits off it than it is to add length to it. Oh, and doing this is the only time I use fly with track, or whatever it's called. Makes things a bit more painless when you're repeatedly laying countless lengths of straight track.
For the first couple of attempts I also use the Undo function to get back to near the starting point, although I treat this with a great deal of caution as RW
will inevitably fall over using it too much. I had three dump files when I was doing this tutorial, so there's no real getting away from it. Take it nice and slow and let the sim catch up with you before undoing the next section and with luck you'll be OK, but the second you forget and get carried away it
will crash.
For the next attempt I usually cut off about a buffer length, as per the screenshot. I would tell you the distance of this curve but RW died before I got the chance.

Needless to say, I chopped too much off so ended up way left of where I wanted to be.
Buffer.jpg
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