I always like it when ground controllers assume that a King Air is automatically more important than a C172. Ok in most cases, they are, but I had this little gem yesterday: At our airport, we have four runways, 2 east/west and 2 north/south, each with a parallel taxiway. We were on the parallel for an east/west runway, holding short of the parallel for the main north/south runway. Taxiing from our ATC designated runup spot at that point to our runway would have us cross the 35L/17R parallel taxiway, and then that runway, and then a straight shot to our runway. As it happened, the King Air was doing its runup at the same time as us, at one of the 35L/17R exits, on the Apron side of the parallel taxiway. Their runup location was about 1/4 to 1/2 of a mile south (and further from the takeoff runway) than us. As it happened, we both completed our runups at the same time and advised ready to taxi at the same time. Ground's clearances went as follows: "King Air XXX taxi to 9L via G A B B2 Cross Runway 17R" followed immediately after by "Cessna XXX follow the king air cross 35L". So for about two minutes we sat there burning avgas while the king air moved on, even though, behind them, we took just as much time getting ourselves ready for takeoff as they took getting themselves ready for takeoff. Maybe its a takeoff order thing, but I don't see how them sitting behind us in line would be any more inefficient than us sitting behind them, and they sat behind Cessnas and Seminoles in the pattern anyway.
P.S. Both us and the King Air were training flights.