Whoops. Yeah, missed that first time around.

The more I play around with the XOR patterns and permutations of row order/orientations, the less I think that these words are meaningful. It's a fairly unlikely coincidence, I admit, for "is" "the" & "keyfile" to appear, but those aren't particularly long words, with "keyfile" being the only exception.

But, perhaps more important--why would they use the term "keyfile" (or "key file") at all? The result wouldn't be a file, it would be a private key. I don't see the puzzle creators using a phrase like "keyfile" when "privkey" or even "key" would suffice, especially when "keyfile" is technically innacurate.

Not to mention generating this phrase requires a series convoluted steps:

1. Arrange 6 out of 8 rows in a pattern that doesn't appear anywhere else in the painting (to be fair, it may be undiscovered, but the bishop/knight explanation breaks down, for me. It's almost certainly a queen rather than a bishop, and the knight's movement is precise in a way that doesn't reflect the jumping around necessary for this row order/orientation)

2. XOR with 011010, but only after you skip the first bit entirely.

3. Cycle back to the beginning of the 6 rows and rinse/repeat.

What about the 011 pattern that tracks through all of the rows without deviation? Sure, it's possible to encode words and still have that pattern exist, but it's a hell of a lot harder, and--considering the route you have to take to generate the above phrase, seemingly unnecessary.