By the time the Flt Eng and then the Captain had asked me to chuck a bit of extra fuel on-board and hide it, the fuel state on the 10 was often higher than it was supposed to be.
The times I spent shoving fuel up the fin then transferring it back and so on until it just read zero ish and then back and forward between the wing tanks to get it reading correct quantityish, while losing and hiding the extra 1000Ibs. First thing the Eng did on take off was open the fin tank up and watch the centre miraculously top up.