These days, most class racing fleets have ready access to standard tuning information, so there is no mystery about getting the basic boatspeed pretty close to everyone else's. The side effect of this is that the difference between fifth and fifteenth can come down to one bad tack, or a poor mark rounding. You are bound to make a bad one occasionally, but attention to detail can reduce the chances of this. By sorting out the details you will reduce to a minimum the time spent with your head down in the boat unscrambling a problem. There's no point in fighting your own boat as well as the opposition!
Consider mark rounding, as I round the windward mark and start reaching, there are lots of controls to be dealt with:
Which of these do you think is most important?
I'll come back to that, but for the moment just think about the loose foot and mast ram controls. At the start of the reach I slacken the foot, tighten the ram. Assuming a triangular course, I do the two reaches, and approaching the leeward mark, tighten the foot, slacken the ram, but on the other side of the boat. During a three lap triangular race, the spare end of the loose foot control will migrate from the starboard to port side of the boat, while the spare end of the ram control line will migrate in the opposite direction. Thus I should make sure that there is enough spare line on these controls is enough to allow for this, and make sure that before the race starts I get the spare ends on the correct side of the boat. Simple when you think about it, but how many of you do this? Conversely how many of you have been approaching the leeward mark in close competition and been unable to make the desired adjustment because the spare control line was in the wrong place?
I'm not sure if I like the idea of having this much spare line on the controls, because they easily get tangled, so you can use other techniques, like tighten up the loose foot before the gybe, and release it afterwards - quite a good idea in strong winds anyway - thus getting the spare line in the right place. Or you can readjust the line during an idle period during the race. When Carol was crewing for me, she would often untangle the control lines and drape them over my forward leg when approaching a mark. A pretty clear hint that some alteration was necessary, but at the same time making it so much easier to get it done. Another fine detail! Incidentally these lines all have knots on them don't they, but are the knots big enough to stop the tail going down the self bailer?
Now for the centreboard. In my boat I find the position of this is not that critical, except at the gybe. To avoid wasting time discussing it with the crew, I have a line drawn on it, which should be lined up with the plate capping for the gybe. Simple and it avoids wasted effort! There is also a control line which allows the thing to float up to the approximately correct height at the start of the reach, and then it can be fine tuned if necessary later.
Back to the mark rounding question. The answer is: none of these! The most important thing is a smooth rounding with minimal rudder movement, co-ordinated adjustment of the sails, no violent rocking of rig. The rig adjustments are in the details, but, before your mark rounding you should have worked out which is more important for you at the time. For example, if we are beating against the tide, then the reach will be finer than usual, so I would not touch the loose foot - don't want to be overpowered - or slacken the rig. Probably slightly straighter mast, a bit less kicker.
Conversely, at the same mark when the tide has turned I would want to get on a very broad reach early. Thus board up, foot off, leeward shroud slack are more important. This way I can get downwind - and this means uptide - of boats around me quickly, placing me in a better tactical position.
Different types of boat have different controls, different sets of problems, but I think that if you start thinking about them you can find details that you are not happy with, and gradually learn how to put them right. Sometimes this is not easy! I know that I can gybe around a starboard hand mark with no problems, whatever the wind. Around a port hand mark I tend to have trouble. I have analysed this and know that it relates to co-ordination of foot placement, and the correct time to swap the tiller extension and mainsheet hands. I often go out and practice in medium winds so as to improve, but even so I can get into a mess during a race. Details... details... details....!