Dave...
Thank you for the clarification on the circumstances...nicely done.
In an age where aviation is becoming increasingly complex and demands on crew ever more focused on high levels of safety, something as obvious as a single language for communication should not even be considered as a subject for debate.
Language is no more than a tool... like any tool it has to be effective in its task and it has to be used correctly...I rather think that the fatuous objections to the tool made by some contributers here is less to do with the need for the tool...more to do with the country in which the tool was made...
As I said once before here...none of us flying today made the decision in favour of English being the accepted language...nevertheless, it is.
In all likelyhood.. if the decision was reconsidered by some safety commitee today I would be willing to bet that English again would be the language of choice .. for the very simple and obvýous reason that it is internationally the widest spoken language in the world. Either as a first language or as a chosen second language. ( Before anyone stars quoting China...I did say Internatonal )