Kham... I have been thinking of making the timer into a second timer.  if you set it to 2 minutes.. you hardly lose a single trap but you pull some up that are empty.  if you do three minutes, you lose some but they always have crabs.  I have been thinking of trying 2.5 minutes but to do so i need to alter the script to do seconds.  You are skilled enough to do that with ease.  Skill level may play into it some too.  i have been unsure of how much a high skill leads to them filling and skinking faster or low skill losing them for whatever reason.  i haven't payed it enough attention to know for sure.