If they played a lot, yeah. Thing is, once you get past the initial materia slots of an item, the chance of successfully melding begins to drop exponentially. I think it's something like 45:22:8% depending on the extra added, give or take some variability. To slap on those last 3 would probably take a few dozen materia per piece of gear short of some insane luck. If this guy had hack swapped items or exploited leves as had been allegedly possible, then materia supply would be a non-issue. However, creating that many +craftmanship on your own would take a while.
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