Before you can fish fast-slow you need to learn the water you are fishing. The only way to learn the water is to fish it and fish it thoroughly. Maps can help, and so can seeing the lake at low water, but the most important thing is to build in your mind an index of visual landmarks. For example, being able to pull up on a spot and put your cast right between the green bush and the small brown rock, out about 100 feet on the big boulder that you know is there – that is the key. Doesn't do you any good to remember approximately where something is. When you're fishing fast-slow, you need to know exactly where your target is to be effective.
For some people, landmarking might come easily. For me I have to work at it. I have to put my focus on the mechanics of fishing on hold and think – OK – let's line things up here and remember exactly where this spot is. It's tedious. Sometimes I'm out there practically talking to myself going, “second tree, tip of second dock, and make sure that hill is directly behind you”. But you have to do it. Because lakes change, water levels change, trees disappear, and you need landmarks to make sure you are in the right place BEFORE your boat is over it. It takes years to build the mental lists of spots at each lake, but if you continually focus on it you can speed the process along.
Once you have the spots, you need to start figuring out when it might pay off to fish fast-slow. If I'm going to fish fast-slow it's usually because I get tipped off that I need to get moving. If I get bit immediately after starting fishing, I start thinking about fishing faster. If I get several quick bites, then I really start to get ready to move. If the fish show any kind of pattern, then it's definitely off to the races. It might only take two bites to tip you off to what is going on. People talk about listening to the fish… well listening to the fish is when you get two bites right off and they show a pattern. That's what listening to the fish means to me anyway, and it plays right into fishing fast-slow.
If you see the pattern, or you just suspect the fish are biting and you have your landmarks of known spots, then you can start your run. I'll usually pull up a good ways away from the spot I really want to fish and try not to throw a wake over it. Time and time again I find that bass do not bite when boat wakes are going by. It almost never happens, so avoiding it is a no brainer! Then I use the trolling motor to get into position to put a cast right on the best spot. The only time I won't cast to the best spot first is if I'm in my kickboat/float tube and I know the fish can't tell I'm there. If I'm in the boat, I lay the first cast out to land right on or right past the most prime spot. Why screw around and let the boat get closer? Time and time again I find that the biggest fish do not bite when the boat gets close to a spot, so putting the first cast on the best spot is a no brainer once again!
So now think about it. You pulled up, cut the motor and crept in with the trolling motor then made one cast to the best spot. If the fish are in a feeding mood and you approached the spot right I believe you've covered 70% of your chances on that spot with the first cast. The next cast is another 20% of your chances, and any casts after that are going to give you diminishing returns on the other 10% of your chances. If someone watched you pull up, make three casts and move on, they might say you were fishing fast. But effectively you may not be fishing fast at all! You're fishing fast-slow, because during those three casts the guy who knows what he is doing makes sure his bait passes the key spot at the right speed whether that means fast or slow.
And the speed of the bait in the key zone is the slow part of the equation. No matter how fast you move from spot to spot, you need to put the bait on the key spot at the right speed. If you were really dialed into a jig bite where the bass wanted a slow presentation, but you also knew the key spots and had the fish patterned, you could make three one minute casts to one spot and then bail. Wow, you just spent three minutes on a spot, you must be fast! Not exactly… you're fast-slow.
Depending on how close your spots are together you might go between spots on the big motor or the trolling motor. I think this is where people really get confused because they see a guy casting with the trolling motor on high bypass and think he's actually trying to get bit doing it. Really the guy is probably just keeping his lure wet on the odd chance a dumb fish might come up and grab it. I do it all the time while moving between spots just to keep my lure wet and sometimes I do get a fish just randomly, but it's rare. The key is the 20 second window where I let off the trolling motor and let the boat glide up on a spot, then fire out and work my bait in the key zone before moving on. That's fishing fast-slow. It's no fun for the guy in the back of the boat getting dragged along, so it's not something I do a lot when fishing with someone else, but when I'm by myself it's game on if the bass are biting.
Overall this is an advanced technique, not something that is going to click for someone just getting into bass fishing. But it's important to at least understand the concept and work toward being successful at it. Many of the top tournament guys fish like this, but they're not going to take the time to explain everything that is going on to the non-boater who doesn't know the spots like they do. They're not going to explain that in pre-fish they patterned fish on the shallow side of points around shale rock and that's why when they run up on a point they only cast there 5 times and then leave. They're not going to explain that they've fished a certain bank so many times that they know the key areas, the little pieces of wood, the edges of the grassbeds, etc and that's why they hit it and go fast for 100 feet before slowing up again to make a real cast. If you're not paying attention to the countless little details of each area, you need to start so that you can pattern like this too and move fast-slow through the spots.
For you trophy hunters, this is just as much a trophy technique as it is a tournament technique. You just have to be more patient on the approach and more sneaky to get the big bite. I figure if I take 40 full day trips for bass in a year, I might hit 4 days where big bass are legitimately on a bite. If you get that whiff that the big ones are chowing down and you can run a big fish pattern fast-slow… that's when 50lb limits will start dancing before your eyes. These are rare days ... days I dream about at night. But those kind of days do exist and if you've practiced the skills, landmarked the spots, and paid attention to those first few bites, you might break 50 doing it. It's out there.