Yes, I can see what you are getting at. However, although I didn't allow any time to re calculate the drift after applying the SCA and therfore that would have put me off track, I see you have allowed one whole minute, which puts you over a mile off track at the conclusion of 4 minutes. The drift calcualtion in real life should take less than that - I would reckon more than 15 seconds is excessive so it would happen in less than a mile. This would put you about a quarter of a mile off track which in the scheme of things is nothing when you are trying to find your next turning point. And my example of an extra 60 knots drift is excessive - I used that figure to keep the maths easy and to illustrate the point. If the wind is more than 15 knots more than planned, I would say that was unusual. This would make the error 1/16th of a mile at most.
I was telling you how it's taught at the RAF Flying Training Schools. I'm not too concerned how to refine the technique for my own use as I don't do much of this sort of navigation these days. Most of my navigation is now done by a triple IRS with GPS updates and with my feet on the footrests while reading the newspaper and drinking coffee! And I doubt the RAF are going to change their technique to include a second change of heading to make the track correction extremely accurate in the case of a cumulative error. That would make the tecnique too complex for the environment it was designed for.
When your at low level in turbulence so that you can't read the map properly and you're contour flying and looing out for other aircraft which may be trying to bounce you, the KISS (Keep It Simple Stupid) principle is a good one.
You have to remember that ther are a lot of variables in navigation, especailly at low level. Are you flying the exact speed? Have you recalculated the drift correctly? have you assessed your track error correctly? When you take all these into account, you will see there is a heavy element of the TLAR (That Looks About Right) technique involved.
The level of accuracy you advocate just doesn't happen in real life.