I know and see your point Joe..."BUT"...I was close, personal friends with Tom & Mary Leschorn (Even bought their old house) and Tom did "not" mark all of his work. GCTOM has a splendid example to prove so and I've seen a dozen more.
Gail White also had un-marked custom RMKs as well. My point, simply being, it ain't something new.
Stay Sharp, Capt. Chris