Based on the little bit I've learned about the way Evans worked that's a good assumption. Harmonic signposts not necessarily meant to be played as wrote. He never really rehearsed his groups, so a brief explanation or impromptu "chart" to convey the general plan for a recording, with plenty of room for improvision within that context, was probably more often that not all he ever offered up.
Perhaps skeith could be more specific in what he means by "more complicated"? There is not much harmonic substitution that I can hear in the versions of the tune I am familiar with. However, there are a lot of extensions in the changes Evans is comping, which is standard practice among piano players after the late 1950s. If by "more complicated" you mean that you are hearing 9ths and so forth where none are notated, you may want to find a jazz theory book to familiarize yourself with typical chord/scale theory and notation.
Right, I was referring to the fact that other transcriptions have chords with more extension like 9ths,11ths, 13ths, augmented chords and the like which is not really how Evans wrote out the changes above.
Yeah, it's common practice to write out chord progressions without all the harmonic detail (which is usually left to the performer to choose). I often will just write "D7" and let the player choose what extensions to add. If I want something very specific I'll write a more detailed chord symbol, like "D9(#11)", etc. I think the goal is to allow more interpretive freedom and avoid restricting the player with too much specific information.
I'd forgotten about the slash-through-the-7 style of writing chord symbols. That was confirmed by looking at the other "lead sheet" (from the Riverside booklet) on Time Remembered. I'm more familiar with that tune and clearly saw use of the major seven slash. Good catch Glenn!