While I reading through Jake's explanation, spot on by the way, I thought about other issues that have not been mentioned. Boat speed and boat handling. If you are losing by a couple of boat lengths and wonder how you could have them back then a lot of what is mentioned here applies. But if you are 30 seconds or more behind you need to look within. Do you have pace with the other boats? If yes then, do you have equal boat handling skills? I am not only talking about whether you think you are steering and turning corners correctly, also how are you meshing with the crew, providing you are sailing with one? If you are single-handing against double-handers I think you are at a disadvantage tactically. It is beneficial to bounce ideas off of someone else.

Just trying to gain some different perspective:
Dan