Planing rail bands without on the fly adjustment?

I can do a pretty decent job doing rail bands with a borrowed modified Hitachi. Now I bought a Wen. I heard in Aus guys did rail bands for many years using unmodified planers(?) Any tips on this approach?

I used a fixed depth Makita planer for years. The technique is to stagger cuts so that the end result is close to the depth of cuts made at various sections of the rail. Hard to describe. First cut is full length, second cut is 6” shorter on both ends, next is shorter. The center area is now deepest area tapering towards both ends. Then one cut down the length of the bevel to level it all out. Hard to explain the process. Imagine if you had to do your bevels with a bench plane. More cuts in the middle and less towards ends to get the bevel to the desired contours. I learned to shape with this fixed Makita so my whole shaping process was developed with that in mind. Imagine the finished bevel you want and stagger your cuts to get you close. I sometimes finish the bevel with a surform to make it perfect, but after 350+ boards this way I have gotten pretty good at getting really accurate with the fixed plane. I do have a modified hitachi and an Accurate with the adjustable depth, but don’t use them much, as concentrating on making the adjustment during a cut is not as easy. Hope you can figure out what I am describing.