I reckon the guy in the article was referring to COBOL basically having fixed sized data structures. Having all your data structures of a fixed size does allow

I reckon the guy in the article was referring to COBOL basically having fixed sized data structures. Having all your data structures of a fixed size does allow for alot of optimizations that would otherwise not be available. However, you can make fixed size data structures in any language, and the benefits of this is somewhat moot with the large caches and fast CPUs (compared to IO) of modern computer systems.