That is exactly right. IMO, if you are responding and contributing into the discussion, that is not considered as a spam, not unless you jump from topic-to-topic writing whatever comes into your mind without a care just to compose/construct sentences to reach the minimum words of 150 is most probably considered a burst posting. Just like you do too, I am also someone who can keep up with several subjects at the same time, maybe it is called multi-tasking or so, but regardless of that, it is something that needs constant practice and requires you to voluntarily control your focus so that you won't mixed up all your replies.
That's right. That's why if a topic is too many replies to the OP or too many replies after my post, we have to spend more time to understand the point of the conversation. That way I'll be able to see if I have something to add or not to the subject.
Of course, sometimes, we can repeat one or another information that has already been said, but if we are original and genuine, we will certainly present that same information from another point of view that can help the debate.