I noticed that in his chapter "Against the Sicilian - 1.Nc3 c5 2.Nf3" Keilhack took time to digress and address "The French Marshall" connection (1.e4 e6 2.d4 d5 3.Nc3 c5), where he mentioned my 1988 effort:
There is a booklet The Marshall Gambit in the French and Siclian Defenses by Kennedy/Sheffield with interesting material, however, its rather confusing presentation doesn't allow clear conclusions either.Oh, well. In our book Riley and I opted to group the lines of play by patterns of piece development, rather than give example master games (with notes) or structure things along lines such as A1b1(c), etc. (By the way, we wrote back before electronic chess databases were prevalent - collecting the games from books, including those in the White Collection of the Cleveland Public Library.)
I will remember Keilhack's concerns as I prepare All or Nothing! The Jerome Gambit, my magnum opus on my current favorite opening.