Let me have some fun with this dire and final statement of "?fact?".
Ignoring the chatoyance for now. Chances are, unless one has a very prize flitch rather than, what most of us work with, a random pile of planks from various trees, one is going to have changes in chatoyance even if one holds their tung just right.
Good practice but often a boring, uninspired or down right annoying visual effect may result however. As in "oh look you can see right where the seams are. Looks like a bunch of random boards glue edge to edge".It is a good practice to make sure when gluing up boards to make a wide plank,that all the boards plane in the same direction.
"Oh but isn't the chatoyance even ?!"
If using a flexy bevel down and especially with a non perfected chip breaker and even then good luck and go to it.
If you do not do this,
of course
you'll have trouble planing the whole plank
Unless of course
you were to switch mid stream to a good basic bevel up plane following Winton's sharpening "ridiculousness " to the letter.
then of course
all would be well, you could lay out the boards for best grain camouflage of the glue joints and inspired playfulness of the imagination stimulating effect of the grain and no tear out would result except from the cross plaining scrub flattening and all that would be progressively cleaned up while planing straight down the panel's length.
But then of course there are those who use the chatoyance as a design element to create checker board patterns etc.But also,there will be a different chatoyance(shine) seen between those different boards when a finish is applied.
They would either have to resort to Winton's "ridiculousness" or bussssout the belt sander.
What ever that is.
PS: Ok I lied
I didn't ignore the chatoyance.