I think a simple append of the same line that goes to standard output (e.g. timestamp accepted: X/X (XX.XX%), XX.XX khash/s (yay!!!)) to a separate file will be perfect (at least for what I'm trying to keep track). Any other information related to the specific share could be a bonus for some.
If that's all you need then you could simply
grep the output stream or the file where you store the log.