Intense, mainly because of having to control the syntax coming out of your mouth, and remembering to to say the “bracketing” words (terminators). It was more intense for me than others at the time, because I was better at remembering to say the terminators. 🙂
This was still human communication, though, and context was still filling in a lot of the blanks. So for me, the syntactic challenge far outweighed any notion of semantic clarity. And with second language levels of fluency, you couldn’t always be sure people actually uttered what they clearly meant to say; so you made the kinds of allowances people make in normal languages anyway. 🙂