My local SCCA region, Finger Lakes, had their opening round for for the autocross season this past Sunday. I was a little uneasy heading into it, because the majority of the top drivers went to the Evolution School the day before. I wanted to go, but I balked at the $260 price tag. The instructor (2-time national champ David Whitener) from the EVO school raced in one of the attendees cars too and gave a course walk through to those that went. Fortunately for me, one of my friends walked the course with me and gave me his tips.
Warning: Way Long Post. I tried to keep it short, I swear, but this is what came out;
I have instructed for Evolution a few times, and it is a good program that you can get your dollars' worth with the right approach. The price tag can be misleading with regards to value, because most people expect the 5-7 minutes of seat time you receive at a typical event but with coaching. You will usually receive the equivalent seat time of 15 plus events, or well over 1 hour of seat time depending on turnout/site. A lot of times it can be recommended that you are prepared for the increased wear from the greater seat time, specifically regarding tyres. If the car is to be codriven at the school, the car could see enough time to go through a set of tires in a day, depending on many variables. If you are just looking for a TnT/shakedown day, then certainly there are cheaper/better options to achieve that simple goal, but the feedback you receive can be valuable at an Evo school.
Typically, regardless of experience they will guide you towards completing the Phase 1 course before moving on to the others. For those interested in the program, I find that can be one of the biggest deterrents to some who carry the mindset of 'I already know what I'm doing and have XX experience, I don't need a beginner school.' In practice, this isn't the case because the program, in particular Phase 1 and 2, are very adaptive and taught 'to the need' of the student rather than having a set curriculum. For example, when I get a student who has done 5 events prior, my approach and what we work on is going to be very different from a 20 year veteran(and yes, they do show up for phase 1). This is easy to accomplish given the typical format for phase 1, which begins in the morning with 3 cold runs alone in your car on a special course layout to set a baseline. Then you will make 3 runs with your instructor along. From there you will typically receive some feedback and be given the opportunity to make the runs again. The improvement(or lack thereof) and deviation in your runs is going to tell me a lot about 'where' you are and where I need to start. The driver that ran all of their runs within .5 who's mistakes consisted of overdriving an entry here or there is going to receive a very different approach and experience from me than the driver who was 5 feet off the cones with a 2 second minimum deviation. Someone who needs to work on keeping two hands on the wheel is going to receive that type of instruction, and someone who needs to work on setting up oscillation frequency for a slolam is going to receive instruction to that effect. Phase 1 is intentionally very malleable because of that reason; people of varied skills will be there.
Phase 2 tends to elaborate upon the skills illustrated in phase 1, with an emphasis on the mental how and why of the skills. It will help students understand why looking ahead dictates your inputs, even subconsciously, and how to utilise these instincts to force yourself to create the proper inputs that result in the car best performing as you prescribed; for example. The course layout is also typically different(as sites allow) than phase 1, with a few longer more complicated elements than the phase 1 course which usually consists of a loop featuring an increasing radius and constant radius turn along with a short slolam or offset. In both courses you will run in both directions, which of course turns that increasing radius turn into a more challenging decreasing radius as the day progresses.
From there, you can take several directions. There is a Challenge school where you will usually compete directly with an instructor in your own car, typically via back to back runs and ridealongs. They also offer some two-day events, including a TnT school, which isn't a TnT per se, but rather a course that teaches how to most effectively utilise TnT dates. This includes more advanced setup and testing methodology, and works on understanding what effects certain setup changes make so that you can make intelligent changes rather than relying on process of elimination.
There are also several higher level courses tailoured to specific needs and students, including a datalogging course that works on how to log data correctly and more importantly, how to interpret and use that data to improve yourself. As well, there are other focused courses that target certain types of events and the how to overcome the mental pressures that come with each unique format. Those are typically offered in conjunction with the event during the weekend.
In summary, there is something for everyone really. There are also alternatives to these programs, including other schools as well and many regions/clubs host their own schools/coaching days. This is why I recommend that folks jump in for rides with other drivers, and if you have a local hotshoe in a similar car; offer them to drive yours and ride with them. You'll probably learn something, and maybe come away with a couple of suggestions to improve your car/setup. Most of the programs use a couple of core instructors, and then recruit accomplished locals to fill the gap depending on turnout. As such, like many programs outside motorsports, your experience can vary with the quality and familiarity of your instructor and the site itself. For example, if you are in your second or third year and run all of your events on your region's tarmac site, you probably won't receive the maximum benefit from taking a competition school at a concrete site. As well, attempts are made to pair instructors with appropriate students and cars as someone more intimately familiar with Corvettes is typically going to instruct other Corvette drivers better than say a student with an SRT-4.
As a personal aside, I used to take a phase 2 every spring as a student. Even instructors need instruction at times, and moreso I found that having feedback from another experienced driver was valuable to me as an additional perspective. Someone else watching you can point out habits(not necessarily bad, but perhaps unique) that can give you a better understanding about what you are doing. Even winning every event, it is still beneficial to know HOW you won and WHAT it is that you do that makes you win. That can help you identify what those subconscious secrets are and what you are doing to make yourself fast that you don't even know that you are doing. The braking double-tap, the 'you push the car, you don't pull the car into a turn' and several other goodies were things I had done instinctively for years. One specific teaching point that is now significant to me; I only realised what I was doing and how that was a key to my success after a student in the past had asked me 'why did you do this there?' In answering the question, that student taught me something that day, something I had always known, but didn't know that I knew. He later went onto GTAcademy along with two more students of mine in following year.
Post Script: I quoted Coach above as it spawned my response, however this post became more general information for everyone and as such is not directed at any individual.
Only competition karts which are going fast enough don't feel a thing. The rest is for you to squeeze the few tenths left on the track, as I said, you already developed the correct technique for this kart. 
