agreed, and i have seen an aircraft pushed with the nosewheel chocked believe it or not....they found out when the chocks were laying in the taxiway whilst being disconnected....dont ask me how it held the nosewheel but it did. But my argument would still be WHY woould you want to start up before connection. For starters you would have an unchoked a/c with its engines running, with the potential of moving under power, and secondly, the captain would want to be ready for push ie tug connected before starting engines and wasting fuel. even with an airstart, i have never heard of start up before connection