All you said is well known to me, even without playing competitively :p But it doesnt change the fact, that one side had a huge advantage here and that side didnt win.
I would take 3x Green Granade + Shotgun over 3x Clusters anytime
something that Mazi didn't have. Let alone if you add to it 1x Holy Granade + 1x Worm Select. Danie had a small advantage there. It's not that Clusters are weak weapons. They are just a weak weapon against danie. Apart from Clusters, Mazi had an absolute emptiness in his inventory for the first 30 min of the game, after which he finally found baseball bat.
If you think that somebody has "huge advantage" having nothing in the inventory but clusters, then try to use clusters to kill a worm that is each time standing in the middle a flat girder in a cave, it will always take you 3 turns to kill 1 worm placed like this