@ 90 \(ºº)/ regarding your game:
You didn't clusterpick in the classical sense, a "real" RoR clusterpicker puts all his picks into one bonus, preferably Partha.
Apart from that your style of "clusterpicking" is documented in my M'Hunters strategy guide, although there I talk about clustering a first turn bonus with autogame settings so you get the bonus not initially after picks (
https://docs.google.com/document/d/1NyhCpIQKShAbWGXicO_ph9whV_UyMS-3a7_re0C7R8Y/edit#heading=h.g1s8mzy7wor0 under "First turn bonus play").
Basically your strategy comes down to killing the opponent with your initial momentum which you gain from your income + army advantage after picks. Therefore you place your picks in areas where you find your opponent immediately or at least after turn 1. I can certainly understand how this can win games.