It is most likely FailRP, but most people who know how broken 457 is will use that tactic as they don't wanna bother dying to it for no reason.
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A nerf was suggested to 457 before, Hierarchy reduced the SWEPs damage. Its grow rate broke recently somehow(prob tickrate change? idk) that's what lead to the let him grow tactic.
Xunt said this on the previous nerf thread.