When I wrote The Whispering Woodwind adventure in early 2001, one reader pointed out to me that it bore some stylistic choices and vocabulary that were similar to that of the late Gary Gygax. At the time, it perplexed me because I certainly wasn't trying to emulate his style but I have no doubt that my own influences, including Papa G among them, would have had a hand in shaping what I felt was that Old School style. I also don't doubt that my own sense of what made for a good adventure would have been wrapped up largely in what made for those great adventures from the Seventies and Eighties when I first began gaming. While I didn't run a lot of those adventures personally (I was more of a homebrew guy), I played through them often and also kept up with the rules supplements of the times religiously.
I have since been back in college to finish an undergraduate degree in English and also a Master of Fine Arts in Creative Writing. I doubt the same influences affect me as strongly as they once did, as finding your own voice is a large part of such programs. But I also feel it helped me to better recognize the tone and cadence of various styles when I see them in modern tabletop roleplaying game works. There has also been a recent study that, in a much broader sense, backs up how contemporaries are more influenced by one another than by authors of past times. While I don't doubt this is true, I also feel it is possible that authors who read mostly works from a particular period are more likely to be influenced by the authors they read from that period than by their contemporaries.
Just some food for thought and you can read more about the recent study here.
The Sevy Mercantile in the 1930's. The old school house.