If you look at the blade's geometry, and you think clearly about what needs to happen for the edge to make even contact from toe to heel then the solution is usually plain as day.
If you do it slowly enough on a dry run or two you'll get the muscle memory set.
Takes longer to hone this way since the entire blade isn't in constant contact with the stone through the pass.
Yep. Two intersecting planes form a straight line. You can think of a smiling edge as a series of intersecting planes.
The other way to think about it is that your job is to always keep a portion of the edge in contact with the stone and that this is what the rolling x-stroke does.
If the edge of the razor forms a perfectly straight line, you can keep the entire edge in contact with the stone use a rolling x-stroke with no rolling .
Just ink the bevels with colored ink and you will see where the ink is coming off or not. Re-ink and adjust and repeat until you are removing ink from the whole bevel in one pass.
It is not unusual to have to give the heel and toe a bit of individual attention to get them fully honed, then blend with a few lite laps.
When you hone a razor with a straight edge, you still want to finish the razor with a light rolling X stroke to ensure you have not honed a slight frown with straight strokes.
The quicker you learn and master the rolling X the better your edges will be.
You can see colored ink without magnification, black can look like a shadow.