meh, plenty of (intelligent!) native english speakers do not know all the canonical grammar rules. english contains a lot of what could be considered error corr

meh, plenty of (intelligent!) native english speakers do not know all the canonical grammar rules. english contains a lot of what could be considered error correction bits, so it doesn't usually impede understanding. syntactically perfect english with weird/misused idioms (common among non-native speakers with lots of formal education) is harder to understand in my experience. I imagine this is true of most natural languages.