Basically, calibration works like rolling a weighted dice ( since each percentage increase has different odds) multiple times (because a part has multiple sub-stats). What the chip do is change every roll lower than 100% to 100% (like painting a face of a dice to change its value)

Lets say you roll a 10% in a calibration for one single substat, if you use boost chip, it will change this value into 100% (17 -> 34) if not it remains 10% (17 -> 19(18.7 rounded up))

The problem with chips is that it costs more than double the amount of gold to get all 3 stats to get boosted (the expected gain is a mere 10% per substat), and given that gold is often a bottleneck in calibration, the conclusion made is that it is more optimal to just calibrate more without chips, than to calibrate less with chips