I took a course touching on lexer and parser theory this semester (a sizeable chunk was devoted to regexes and other FSA, but context-free grammars were covered as well).
Over the course of the semester, the prof mentioned that grammars should be optimized to $LL(1)$ whenever possible. Unfortunately, he never explained properly why such grammars are "better." Wouldn't a greater lookahead make for more effective predictive parsing? Or is it considered harmful taking into account physical resource (RAM, CPU) constraints? Or do parsers with more lookahead simply become more complex than they're worth?