A story, and alot of questions

Haha! Thanks for setting me straight Andrew! Now as to the 2 adjustments, I'm going to tell myself there are no stupid questions! I think I picture will help explain my confused state. Essentially, the traveler has 2 cleats, so you can control the sail. 1 obviously controls and moves the car allowing me to change the position of the sail. Thinking about it now, I guess the second cleat would allow me to control the mainsail twist. I think for embarrassment's sake, I won't comment on when to tighten or loosen. Can you confirm and explain? I'm talking about the cleat circled in blue.



Ohh, as a bonus for answering my silly questions, here's a sweet looking wooden cat from the 09' Wave North Coast Championships. I found it's picture looking for the picture of a traveler setup. Looks like it's using alot of Hobie parts, besides the custom hull obviously.

And I stated rotation incorrectly. In heavy air you want to flatten the sail. By pullling the outhaul you flatten the foot of the sail, by pulling downhaul( stock 18 has very little downhaul ability, upgrade to 5:1 or better) you bend the mast on its major axis flattening the sail thru the center and heres my mistake, you over rotate the mast to flatten, limiting rotation makes the sail fuller.
I knew you had crew left and right at the front, it makes the bows dig and its very hard to tack. Had you backwinded the jib the tack could still be made that way but only with backwind. Also main comes in tight while tacking and then out as air comes across.
I tend to be a risk taker in all areas and I get angered by the cautious crowd telling me what I should or should not do. I like to sail in strong air, small craft advisories get me excited. Pushing my limits and the limits of my equipment is where the thrill is for me. I have been sailing cats for 30 years now and I hate sailing in light air, my lake racing shows that.
Sorry if I offend anyone but" if it ain't blowin' I ain't going".

DOWNWIND SAIL TRIM
With an understanding of how tell-tales work, you can keep your sails working at their optimum, especially when you’re tacking downwind. The course that gives the most speed for the least extra distance is about 135 degrees from the wind, or about 90 degrees from the apparent wind (figure 6).
When your shroud yarns are streaming directly across your cat, you’ve got a 90-degree apparent wind. If you sail higher than 90 degrees (to 70 or 80 degrees) the shroud yarns will angle forward of the beam. And if you sail too low (100 to 110 degrees off the wind) the shroud yarns will angle behind the beam. So, to keep the wind at 90 degrees, watching the shroud yarns is critical. You want to sail as low on the wind as you can without cutting off the flow of air across the backside of your sail(s). A good way to get at this trim is to start the run with your sail(s), traveler(s) and/or barber hauler all the way out. From this point, slowly trim the sail(s) in and head up .until the leeward tell-tale begins to lift and flow aft. If the shroud yarns don’t indicate a 90-degree apparent wind, you have to either alter your course or sail trim until they do. Remember, you can’t get a 90-degree apparent wind if your sails are not receiving air flow across their Leeward sides.
Reaching downwind in a series of tacks is something most catamarans do with no problem. However, una-rigged cats with Less than 130 square feet of sail area cannot sail effectively by tacking downqwind with the wind at 90 degrees. Small unarigs just can’t generate enough speed with the wind at 90 degrees to justify the extra distance sailed.

Since we've moved on to the topic of how to depower the 18, I'll toss in my 2 cents...

Changing the mast rotation has very limited effects. I pretty much always have it pointed somewhere between the shroud and the rear X-bar for upwind sailing. The traditional guidelines for the 18 call for increasing mast rotation to depower.

Likewise with the diamond wires, I keep them snug in all conditions and haven't adjusted them in years. Traditional guideline is to loosen them to depower and allow the mast to bend. Although with the comptip, this isn't really required because the comptip can be bent through mainsheet and downhaul alone.

The main depowering tools on the 18 are mainsheet, traveler, and downhaul. Outhaul is almost always kept in the same position- about 2 to 3 inches off the boom to keep the power low in the sail.

As windspeed increases, the mainsheet should be brought in and the downhaul tension increased as well. Doing this bends the top of the mast making the top of the sail flat and twisted and helps keep the CE low. Once you've gotten to the point that the downhaul is completely bottomed out and you have to play the mainsheet excessively, then travel out a few inches. You can also ease the jib very slightly and this will help open the slot between the jib and main. Only ease the jib to the point that the luff has a slight pocket. Any more and you'll just be flogging the sail. Once you've gotten to the point that you're traveled out to around the hiking straps, it's probably time to consider rolling up the jib.

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I may have missed the time to be adding this note, but I recently have been working on understanding and using apparent wind direction. In his book, Catamaran Sailing from Start to Finish Phil Berman has this to say (in his intermediate sailing section)

I am interested in your take on this.