I think RPN works okay in natural language because you can often use discourse- and world-knowledge to guess the verb before hearing it. When reading programmi

I think RPN works okay in natural language because you can often use discourse- and world-knowledge to guess the verb before hearing it. When reading programming languages that may work less well. But also note that, at least in some languages, there seems to be some pressure to move the verb to the front. For example, German is classified as a verb-final language but in main clauses the verb is actually "moved" to second position (subject-verb-object). Final position is only "preserved" in subordinate clauses. This suggests that early verbs may be easier to process.