Depends what altitude u sail

That's the idea...but the problem then becomes maneuverability.

which might explain the experiments with gybing daggarboards?

Nah - different benefit there. The problem with forward mounted daggerboards is that they are so far away from the rudders that they, in effect, make the turning radius of the boat very large...makes it difficult to tack quickly and efficiently. Over the last several years, we've seen (in F18 and A-class) the Daggerboards get located further aft...closer to the rudder. It makes the boat very twitchy but it tacks very quickly.

I'm lost on the whole gybing daggerboard thing - I thought they did one thing (point slightly to windward to help the boat climb to weather better) but after looking at the infusion boards, I realized they did the opposite of that...so I don't know what they do...I don't have a boat with them so I haven't been overly concerned about it!

Sort of...with daggerboards further forward of the rig, the rudder needs to load up more to prevent rounding up, this is weather helm. If you go too far forward it is hard for the boat to bear away from head to wind during a tack because the boat will want to weater-vane around the centreboards (approximately the centre of pressure of hull and appendages).

It is also better to think of the centre of pressure of the sails and boards (underwater part of hull and appendages) relative to each other, rather than their position relative to the hull. The centre of pressure is fairly close to the centre of area of the sails and boards.

A little bit of weather helm is good for VMG, safety and the general feeling of the boat.

some basic explanations.

http://en.wikipedia.org/wiki/Weather_helm
http://www.onemetre.net/Design/Balance/Tune.htm
http://www.sailingusa.info/sailboat_balance.htm

Gybing daggerboards just require less leeway angle (relative to the hull) to produce side force, because they are setup with an angle of attack relative to the hull.

I'm dubious about gybing boards on cats because the leeward hull provides a significant side force when at a leeway angle. If you try to reduce the leeway angle, the boards have to produce relatively more of the required side force, probably requiring more board area, which I'm not sure is efficient.

Lee or weather helm has to do with the center of effort of the rudders as they related to their pivot axis. The degree to which the rudder helm is sensitive to various rudder rake positions depends on the center of the lateral resistance and the drive for the sail plan.

Your links are mostly related to monohulls and there is a different thing happening there. As their hulls lean, the shape of the hull presented in the water changes dramatically with high angles of heal. The boats tend to lift their sterns and drop the nose (since the bow is slab sided and the back wide and rounded). This changes the presentation of the sails to the wind and it angles the keel downward. They develop severe weather helm with too much lean and tend to lose traction on both the keel and the rudder.

Because the angle of most rudders are fixed on monohulls, it's become common practice to think of lee or weather helm as a sole function of the relationship between the center of the sail effort and the lateral resistance center of the boards, keel, or hull. However, this relationship is actually simpler than that. If your rudder is perfectly balanced between it's own center of lateral resistance (or center of lift) with it's center of rotation (pivot axis), there will be no helm whatsoever - it will be completely neutral regardless of the relationship between the sailplan lift and the lateral resistance in the water or any changes you make in that relationship. If the rudder is off-center with it's center of rotation, you will experience helm and depending on which way it is off center, it will be weather or lee helm. That helm loading experienced will be increased or decreased with mast rake or daggerboard position, but it's not the reason you have helm.

Your points regarding monohulls are correct (except the rig moves forward relative to the keel creating a moment that will bear you away with heel induced trim) but they are secondary effects. You need to also look at the boat from aft to see a moment created between the keel and rig which tends to turn the boat to windward.

Most (dare I say all) rudders have their centre of pressure aft of the pivot axis. If everything else is equal and you move the rudder pivot axis closer to its centre of pressure the force on the tiller reduces (ie. the force you feel on the tiller), but the force on the rudder blade does not change. The pivot point is chosen to maintain a managable helming force for a given weather (or lee) helm that is best for the conditions.

I think we're arguing the same thing but our terminology is different. Because most boats want to round-up into the wind and the force on the tiller is the feedback we as skippers feel for this effect, they can basically both be called weather helm.

There is a slight difference between cats and monos but the principles are the same, the various forces on the boat are separated by distances creating moments. Those forces change with heel, trim, sail settings and daggerboard position.