I've been hitting over 5000 threads per day lately: if -you- had
listened to 5000 different conversations today, and another 5000
tomorrow, and two days from now someone went ahead and continued one of
the conversations as if there hadn't been any interruption, would -you-
be able to pick up immediately, or would you have to say, "Hold on!
Give me the background context to this before you start in on the
continuation!" ?

What kind of people read hundreds or thousands of messages a day
(and understand them)? Oddly enough, such people tend to be the
people with a lot of experience -- exactly the kind of person you
hope might answer questions or provide a clarification/correction
if one is necessary. So if you hope that the experienced posters
will contribute to a thread if warranted, then you should make it
easy for them to do so -- by *not* top-posting!