Don Knuth and MMIXAL vs. Chuck Moore and Forth -- Algorithms and Ideal Machines -- was there any cross-pollination / influence in their ideas / work?
There is some evidence: This paper was presented at the ACM SIGPLAN History of Programming Languages Conference (HOPL II, April, 1993), co-authored by myself, Chuck, and Don Colburn, an erstwhile colleague now unfortunately deceased. It references, in turn, a very early work that Chuck wrote when Forth was in what might be called an "alpha" form, "Programming a Problem-oriented Language".

I worked with Chuck from 1970 until 1982, when he left FORTH, Inc. to pursue chip-level implementations of Forth. I know that he referenced Knuth's books and papers for specific algorithms from time to time, but do not believe Knuth influenced the design of Forth in any way. In the time I worked with him, the two men never met. Whether Knuth was aware of Forth or of Chuck I cannot say.