Nice 'thought experiment', Greg. Apart from suggesting one direction that English as a Lingual Franca might be taking (i.e. to reduced inflectional forms), your chart demonstrates the fact that verb inflection carries less semantic 'weight' than does co-text, particularly adverbials. A corollary might be that, if we spent more time on adverbials than on tenses, we might get learners up to communicative speed sooner.

I now think that you make that day a good chart. Actually, I talk and write from now on like this. My family, friends and students after today say "He now speak great English." How do you learn over the years to teach English so simply and effectively? Is now you a teacher use every day this method? I teach many years but know not during those years this way of get all the time students "up to communicative speed".

I think you this day a good chart. In fact, I speak and write is like this. My family, friends and students, said today: "He is great to speak English." How do you learn to teach English over the years, so simple and effective? Now you are a teacher every day using this method? I taught for many years, but do not know in those years all the time in this way the students "to the communication speed."