Last offtopic post from me: Sure, but knife has a closer range than scatty, so the hidden would be even closer to the heavy. Heavy aren't good at that range.
Then with scattergun you need to have a decent aim, while I see many spies coming from everywhere poking me with their knife.
It's just 5 hits. Knife's attack interval is a mere 0.8 secs, which If multiplied by 5, it's still 4 seconds. An heavy won't do much in 4 seconds.
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