It's one thing if a character has deadly aim, that's totally fine. However it's quite another for the character to be able to throw, flick, spit, etc objects with the force of a bullet. That's straight up superhuman.

So I'm wondering if there's ever been any explanation for this? Is it just writers crossing lines between been skilled and being superhuman again? I wonder how fast Lance Armstrong would be in comics? "OMG Lance Armstrong is so good at cycling, he's traveling at mach 5! But he's totally human people."

Not sure I agree. He's scary accurate. If there's a chance it could hurt, he'll make it hurt. In Captain America he was being held in a cell where there was nothing for him to throw. He knocked out his own tooth and spit it in the face of a guard to distract him so that Bullseye could get the drop on him but he did not spit the tooth through the guard's head.

Maybe I just haven't read a story where he did what you're describing. So in that regard, I'd have to say it's on the writers.

It's varied from writer to writer, but Bullseye was killed and resurrected by the Hand at least once. That tends to enhance a baseline human's abilities.

So it's an easy leap that he could launch it with greater force. Pretty sure he's had other enhancements over the years.

He's got an Adamantium spine too as I recall

Spine and legs I thought from being dropped off a building.

I did recall seeing a pic sometime ago I think in a Bullseye respect thread where the guy was in a interrogation room handcuffed, then he spat a through right one of the officer's skulls. It would've been one thing if the tooth hit the officer's eye or went up his nose, but this one just went straight up through his skull like a bullet.

When I saw that, I was like "WTF? So he has superhuman spitting capabilities?"

Then there are some others I've only heard about like "snipering" a person with a toothpick from a long distance that still broke through some thick window and killed someone.

Anyways it's nice to know there are writers who have keep the power of his deadly aim in check. I guess it's just another case of a few misguided writers mistaking skills for superpowers again.