My recent theory is that the more the length of the “bright green” part of the stars for the same final-level player, the faster trainer he is compared to another one with the similar final quality level.

For example, ST Tuncay and DC Demir are faster trainers than DR Aydemir, because even if their end quality is almost the same, their starting point is lower (that means they grow faster than the DR to reach the same quality). This is of course only in comparison.

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