Conventional typing tutor software is for beginning and intermediate typists, and is designed to help a person improve from zero to 60 WPM (vroom, vroom!). To go from 60 to 90 WPM, however, requires different techniques, a different kind of exercise -- a whole different approach to the activity of practicing. 60 WPM is a typing speed that most people who type regularly (or who practice, diligently, by almost any method) achieve. Typing at 90 is more like gymnastics: you've got to do special exercises to get you past normal human limits.
A fundamental principle of Typing Master Class is that fast typing is not a general skill. For example, a medical transcriptionist who could type 80 WPM might drop to 50 WPM with text that had a lot of numbers in it. Therefore, Typing Master Class is not based on fixed exercises; the student is expected to supply most of the material for typing.
Another important principle underlying the design of Typing Master Class is that the wrong approach to typing -- the wrong technique -- can prevent a person from typing fast, no matter how much they practice. Therefore, Typing Master Class has diagnostics which help the student identify and correct problems in their technique.
Finally, the design of Typing Master Class is based on the principle that increasing typing speed is a matter of learning, not just rote exercise. Therefore, Typing Master Class identifies what the student needs to learn, and makes it explicit.
Because of Typing Master Class's focus on conscious, directed, problem-oriented practice, a student using Typing Master Class will develop the awareness (and be made familiar with the approach) necessary to remove obstacles to fast typing -- even those not explicitly covered in Typing Master Class's toolset.
The Diagnostic kit in Typing Master Class starts with an evaluation of the student's basic typing skills -- to determine whether the student is ready for Typing Master Class. A student failing to pass this test is referred to Mavis Beacon, etc. (which could be bundled with Typing Master Class).
The main tool in the Diagnostic kit is the keystroke timing profiler. This allows the student to identify their slowest letter sequences. The source text profiler analyzes the sample text the student is typing to establish the frequencies of the letter sequences it contains. The results of these two profilers can be combined to help the student identify the exercises which will give the most dramatic speed improvements for the selected source text.
Often, a student can type a certain letter sequence in one circumstance but not in another. The anomaly detector identifies these mismatches, and creates exercises which alternate between the slow and fast contexts, to allow the student to recognize the commonalities between the two patterns and transfer their skill from the fast pattern to the slow one.
Repeating an exercise is valuable for only as long as the student is figuring out how to do it better, and getting more familiar with it; after that, the returns diminish. However, once a finger pattern is learned, it must be reinforced or it will be forgotten. Typing Master Class is savvy about the optimum timing of repetitions, both immediate (for getting familiar with the pattern), and delayed (to reinforce the learning). Also, Typing Master Class adjusts these timings based on the student's own style of learning.
A big part of typing fast is learning how to think about words, how to parse them into pieces which can be typed quickly. Although Typing Master Class does not have fixed exercises per se, it does have a database of "hints" for many hard-to-type words; if a student has trouble with one of these words, a hint about how to think of it and some special exercises are suggested.
Of course, not all keystroke combinations are equally easy, and Typing Master Class knows that. It has a database of formulas (based on the ergonomics of typing and studies of fast typists) to determine the muscular requirements of various letter sequences. This information is used to put the student's letter sequence timings into perspective. This approach allows Typing Master Class to suggest the exercises which the student is most likely to benefit from: sequences which are slower, not by absolute timing measurements, but in comparison to how well they ought to be able to do them (based on their other abilities, and what can be reasonably expected).