Yeah... you're overthinking it.
Your "success rate" is based off some prior data. In the example that you have 40% in a class, and then get a 50% on a test... if the 40% is out of a million points overall, and your test was a total of 2 points... it's probably not going to show on your final grade.
Also, you're using two different scales here. You have a percentage based on some number of previous trials, then you're saying a single instance of 0% and a single instance of 100% are going to shift the results more than the other. You are comparing a discrete scale vs a percentage, which doesn't really make sense. If you're going to do that, you should stay in the same scale:
2/5 -> 2/6 --> 3/7
This is "success rate" per trial.
Also, it sounds like you're assuming the base number doesn't change (or something??). While it's true that since there are less instances in the first failure, the second even hasn't occurred yet, so it isn't being considered in the total sum. Once you move to the next step, there is a greater data set, and all points are weighted the same (since you're taking a running total).
4x Dunlop Bio 200 L // Babolat Sensor
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