No, because dropping the first packet in a TCP connection means that the handshake doesn't complete. Tarpitting allows the handshake to complete and then keeps the connection open, which will keep the client connected for a much longer time than if a host doesn't respond to a SYN packet at all. http://en.wikipedia.org/wiki/Tarpit_(networking)

That's not tarpitting. Tarpitting involves keeping the connection open in order to tie up the resources of the attacking host.

Or just add some salt?

Hasn't that already been done?