Sorry if this was already suggested:
Step 1: get two blueprints. It shouldn't matter which two, skill levels, etc.
Step 2: On each bp, do 1k clicks consecutively, tracking gains/losses on full quantity (for condition I would think at least 10k clicks would be necessary.) A breakdown per 100 clicks is fine, but not necessary. Calculate average profit/loss per click or per 1k, doesn't matter.
Step 3: Do another 1k clicks on each bp, but this time alternate them in sets of 100 (or 50, or 10, or 1, it shouldn't matter.)
If there is a personal loot pool:
1. The alternating sets will not be equal to the baseline sets. (Although I have seen series of crafts that do follow a 2 losses/1 win pattern, so three bp's can be used in this case.)
2. The gains in alternating sets should follow losses, and vice versa. The % chance that a gain run follows a loss run would be much higher than 50%.
3. The gains in alternating sets should make up for losses in the previous sets, and vice versa, within about 5-10%.
If you wish to control for COS, you can use qr bp's from the same level and book, but if there is a personal loot pool, QR, skill level, etc. shouldn't matter.
If there is no personal lootpool:
1. The alternating sets should be equal to the baseline sets.
2. There will be no pattern in the gains/losses. The % chance of a gain run following a loss run is very close to 50%, within +/- 5%.
3. The amounts of gains/losses will not equal each other, the variance will be +/- 10%+.
In this case, I would advise to control for cost per click, probably the cost per click between the different bp's should be less than 10 pec.
If you are getting a lot of negative runs (or only negative runs, actually), break even point can be recalibrated to 90-95% and profit/loss calculated from there.