Any other killer, who was not seen by Baker and Truly, or anybody else for that matter, would not have the requirement to come down the stairs so quickly. He could have hidden somewhere in the building and, posing as an law enforcement officer, use the commotion to leave the building later. If you don't get a simple concept as this, there is not much anybody can do for you. Ignorance is bliss, right?
Did you misspell a word?
If you don't get a simpleTON concept as this, there is not much anybody can do for you.
There's a lot of assumptions in your implausible scenario.
An alternative scenario, involving another shooter than Oswald, is always going to be an assumption. Just like your claim that Oswald came down the stairs is an assumption. There is nothing implausible in my alternative scenario.
Any other killer, who was not seen by Baker and Truly, or anybody else for that matter, would not have the requirement to come down the stairs so quickly.
Except to escape. Can you nominate a prominent murder case (hit) where the hitman did not immediately flee the scene of the crime?
A guy who doesn't belong in the TSBD, running down the stairs, directly after the shots would stand a far greater chance of being noticed. It would involve a high risk of detection.
He could have hidden somewhere in the building and, posing as an law enforcement officer,...
No witness saw a law enforcement officer in the 6th floor window firing a rifle.
Really?
How would any witness know what the profession is of the man firing a rifle?
But I didn't say he had to be a law enforcement officer. All he needed to do is pose as one, by flashing an ID. Just like the man Officer Smith ran into behind the picked fence on the grassy knoll.
...use the commotion to leave the building later
What commotion was that? Please provide evidence of a specific "commotion".
Police officers storming into the building...
Within minutes after the shooting the place was flooded with police officers, Secret Service agents and God knows who else. Tom Alyea managed to sneek into the building and nobody paid any attention to him. A guy, pretending to be an officer, calmly walking out of the building wouldn't stand out either.