Removed RSI comment.
Used valgrind_undefined in an appropriate place.
Removed RSI comment.
Replaced RSI comments with a comment.
Removed RSI.

We do not have an actual ordering until unsharding, so we cannot push said
datum stream "down to the shards".
Added an RSI.
Removed RSI about funcall_term_t.

Now I do know what it is.
Dropped obsolete RSI comment, improved others.
Added an RSI comment.  Reverse progress!