Just before my departure for Noosa here is the next set of answers... (I have a good feeling about those Noosa fish btw :-))
Q1 I have some other questions that have been niggling me slightly, such as my leader. The minimum length I recommend for trout fishing is one and a half times the length of the rod. In saltwater everyone seems to use a nine-foot leader. I realise that this is because we do not use such fine tippets and besides the saltwater flies are bigger, more wind-resistant and require more energy to turn them over. I always use a tapered leader, these being cheap, long lasting, giving the smoothest transfer of energy and without knots. Many saltwater flyfishers I have read (I haven't met many) construct very complicated leaders using special knots and secret formulae. What do you guys do? :-)
Bruce: I don't have many set "rules" about saltwater leaders. The one I do think is important is that the butt diameter be big enough. I've seen many anglers have trouble because their butt section was too light, but NEVER because it was too heavy. Don't build leaders based on the strength of a section (except the tippet). Using 40 lb. mono might seem adequate for a SW leader butt, but with some monos, 40 lb. is only about .020", light even for some trout leaders. Build by diameter only, it is the mass of the section that turns over, not the tensile strength, OR STIFFNESS. For bonefish type leaders, .026" is about right. Tarpon leaders should have butts about .030" (which may well be over 60 lb. test.). Use limp monos as they are easier to knot and straighten, and turn over every bit as well as stiff monos that are hard to work with. Judge the length of a leader by the conditions at hand, longer for spooky fish in clear shallow water, shorter for less sensitive fish in murky water, cloudy days. Leaders longer than necessary are difficult to cast, especially with weighted flies. Unless the application requires something out of the ordinary, the leader butt should be about 50% the length of the leader (60% if the leader is longer than 10 ft.), the taper 25%, the tippet 25%. For high wind, longer butts, shorter tapers/tippets work better. There are some very complicated leader formulas that work well, but not better than simpler 50/25/25 leaders. Casting skill is still the answer, good casters can make any reasonably good leader do the job.
Tom: I use a wide variety of leader configurations and length for different situations. A 9 foot leader is a great starting point but will not satisfy every situation. Here are some examples: If I want to place a fly 3 inches in front of a tailing bonefish on a slick calm day, the presentation is going to be difficult and splashy at best with only a 9 foot leader. If I lengthen the leader out to 12-15 feet the presentation will immediately be more delicate. As for the special formulae, some leaders require it. For instance, a Bimini Twist is considered a difficult knot but it is really easy. It is used to double the line without sacrificing any strength. This strong double line can then be tied to other material of different diameter or different material in a stronger way than if it was just a single strand. The knots look complicated and sometimes are but they serve a purpose. Knots evolve as fishermen do and alot of times leader configurations are made easier by inventing new knots that are easier to tie and replace the old knots. With the advent of Flourocarbon, many knots have been replaced because the material is so much easier to work with and stretch out. I try to make my leaders with as few knots as possible and with as simple of knots as possible. The fewer knots, the fewer that can break. I have invented some knots that I use daily and also watch for any knots that I can incorporate into my fishing and make it easier. Just remember that the simple leader is may be stronger than a complicated one because you will learn the knots well and tie them well.
Brad: I use this for 80 percent of all saltwater applications. There are situations where you need something a little different, but it normally can be corrected by changing what you are doing to the tippet section. I start with an 18-inch piece of Mason Hard Type. I use 30 lb test on my basic saltwater rig. You will want to tie a surgeon's loop in one end of the Mason, as you will use it when you connect the leader to the fly line via the loop to loop. I use Ande Backcountry 25 lb. test for my next section, and it is also the longest. I want 24 inches. I then use Ande Backcountry 20 lb. I want 18 inches here. I then use another 18 inches of Ande Backcountry 15 lb. Finally, I add another 15 inches of Ande Backcountry 10 lb. Now, for the mathematicians in the room, you are now noting that I have a leader that is 93 inches long. (But Brad.....a 9 ft leader is 108 inches? What gives?) Enter the equalizer. The final step is taking a 15 inch section of mono and tying it to the end of the leader as a tippet. Now, I am going to freak you trout fishermen out on this part. We are going to use what is called a shock tippet. That's right...a 15 inch piece of Ande Backcountry 20-25 lb. tippet depending on what you are fishing for. This is not a delicate presentation leader, but a "big ugly, hold on to your butt, that fish hit so hard I almost wet my waders kind of leader." This tippet will keep the big toothy critters from eating through your line. In addition, about 80 % of the force of any fish is felt in the first 15 inches of the leader. To that end, we need that section to be as strong as we can make it. This is why tarpon fishermen in south Florida use 80 and 100 lb shock tippets on their tarpon leaders. Anything else won't hold up.