Let's assume a medieval lord named Gary I of Flowers lives in a "Europe-ish" continent with no gun powder or magic. Somehow, he's aware about modern warfare theory. Maybe he found out a time-traveler who happened to be an expert in warfare (and nothing else!), or maybe he's just ahead fromof his time.
Gary is an excellent general of his times. He's adaptive, open minded, and well respected fromby his soldiers and knights. He also has plenty of time and gold to modify his army. There is no "culture shock" from any unconventional tactics Gary would use. At least for his men...
By modern warfare theory, I'm not speakingtalking about using modern equipment, - Gary doesn't have the means nor the technical knowledge to produce those. I'm currently thinking about using principles, tactics, strategy and knowledge about warfare generals of the 21th century to master and adapt it to a medieval technology.
My question is, would modern warfare theory be useful to Gary against his enemies? How would his medieval army, tactictactics, and strategy change using only resources available at the time?
Of course, it may change society as a whole, and ends the Middle Age way sooner than expected, but I'm not interested in that. I want to focus on warfare and everything directly related.
The only question I found in this site related to mine is this one, Mechanized infantry of the medieval age , but it only focus on one thing. I know my question is very open and maybemay be unclear. I would love to read any feedback.