Tyson goes out of his way to make sure people underestimate him, to seem weaker and less intelligent than he actually is, to gain the upper hand before the battle even begins.
He is the friendly face of the web, someone kind and gentle to coax people unwittingly into the Moriarty Mirrors’ trap. That Tyson genuinely is a kind caring person helps the authenticity, but it doesn’t change the fact that he is bait. He needs to appear harmless, approachable. He’s safe.
Don’t worry about him. Turn your back. Go on.
He is an excellent fighter and he knows how to survive better than almost anyone. However, when presented with a threat or someone he knows intends to posture about being a credible threat, Tyson’s first move will often be to curl in on himself, make himself smaller and back away.
Subconsciously people then think he’s not that bright and not a threat, especially when they know a thing or two about fighting, the most basic survival tactic people are taught is to make yourself seem bigger: to puff up your chest and stand your group.
It’s a simple trick, but it’s enough for people to dismiss him for a more obvious threat in other members of the web. Why worry about the cowering fool, when there is someone with the eyes of a killer who doesn’t flinch in the room? They call him Pup, he’s obviously not dangerous. Just a whelp.
Tyson also makes himself seem less eloquent, often avoiding the works he wants to use and ending up with short clunky sentences instead, but that’s about working around his stutter rather than a deception.