That little voice inside your head knows what it's talking about.
"Never underestimate an adversary" is an excellent axiom of life, be it applied to warfare, law enforcement or personal defense. If I had a dollar for every time I've heard the bad guy described as a "knucklehead," "critter" or in much more politically incorrect terms, I would be in the top 1 percent tax bracket. Just because someone is "different" due to their choices of lifestyle or perhaps mental affliction does not mean he's stupid.
One example I had of this was when I arrested a young man on an otherwise common failure-to-appear warrant for drug possession. His mother (who, of course, said he was not home) let us in. When I searched the upstairs, I had both gun and flashlight in hand, a violation of our rules that mandated a justifiable reason to draw our sidearm, which I did not have.
But I felt something wasn't right, so I did have my gun and flashlight in hand and directed them into every room, bed, crawlspace and closet I searched. When I got to the back bedroom, I found our guy under his bed lying on his back.
He came out willingly, and that was the end of the arrest. Nothing out of the ordinary, other than how he hid under the bed. Most of the fugitives I've arrested, when coming out of a sound sleep or taken by surprise by our presence, went under a bed on their stomachs, as this is the fastest way to hide.
Six months or so later, I had to go after the same guy again for failure to appear. We went back to the same address at the same time of night and re-enacted the same scenario, including searching with gun and flashlight in hand. Again we found him under his bed--again on his back.
This time, I thought about his body position. Doing the same thing twice was not a coincidence nor a sign of stupidity. While my partner held him, I searched in and around the bed looking for something. Finding nothing in the usual places, I lifted the mattress and box spring together to look underneath the box spring.
My efforts were rewarded by finding a nickel-finished, fully loaded Smith & Wesson Model 10 .38 Special with four-inch barrel stuck in there, with the gun pointed right toward where I had looked under the bed each time.
I still had no legal justification for having my gun out other than my gut feeling that something was "wrong" on the first arrest. And it would be a stretch to claim his hiding on his back was enough to justify doing so the second time, right along with searching around the bed after we had him cuffed and could leave the house. Of course in hindsight it made sense, since he would have to be on his back to get off a good shot with minimal body movement on his part with the secreted handgun.
The point here is that I didn't assume he was dumb because he again hid under the same bed in the same position in the same house and at about the same time of night. (It also proves that it pays to listen to that little voice telling you something just isn't right.)
PS: Yes, we did have a conversation about the gun ("Gun? What gun?") But this denial aside, we did have a meeting of the minds, and he agreed that it would be in both our best interests if he never caused me to have to arrest him again.