Since you are unable to explain the alleged absurdity with a rational, evidence based argument, there are two possible reasons: 1. There is no rational, evidence based explanation to support your claim or 2. laziness. I know it is not due to laziness.

Right, but you know the response: JFK was just saying that until he got re-elected, he was appeasing the "national security war state." Once he was re-elected the "real" JFK would emerge and expose all of this war hysteria and end the Cold War. And it was for that that he had to be killed. How did they know this? That this real JFK was going to do all of that? Something that RFK and McNamara and Rusk and Bundy didn't know? Don't ask, what are you a CIA apologist?, just go with it.

The conspiracy crowd has created an alternate universe. It's the only way their conspiracy can work. Two Oswalds, fake this and fake that, witnesses being killed, coverups for decades, a compliant media, and here, in effect, two different JFKs.

Yes, conspiracies happen; governments engage in them and then lie. But sometimes they don't happen and sometimes the government isn't lying. You need to be able to tell the difference.

If you want to suggest that it is impossible you need to show that what I have portrayed in my model is beyond the range of what is possible. You can’t do that by ball parking. I have JBC’s shoulders turned to a bit less than a 2 o’clock or 60 degree position - certainly past the angle of the forward car direction to the sight line to Zapruder.  What do you determine to be the maximum possible angle he is turned at z193?  And explain why. I have the angle of the bullet relative to the direction of the car at z193 at about 16 degrees.  What do you determine to be the maximum possible angle at z193?  And explain why.  That would be a start.

Then you can start to explain what evidence makes it impossible for JBC to have his left leg out to the side. Try sitting on a seat cushion on the floor and keep your legs together. Hint: you will find it uncomfortable if not painful.

Your model does not even pass the eyeball test. Not only do you grossly exaggerate JBC's shoulder turn, you also have him leaning toward the right side of the car to get him out of the way of the bullet exiting JFK's throat. On top of that, you keep his left leg flared out in an unnatural position for someone who you showing making and extreme turn to the right. It is a joke as anyone who compares Z193 to your goofy drawing can easily see. The fact you have to exaggerate JBC's position to make your theory seem possible demonstrates that it is not.

I can only judge Maher's views on the JFKA based on his comments. His skepticism about the SBT parrots the objections to it that were presented in Oliver Stone's fictitious movie. It's possible he could have got his ideas from other sources which have raised the same invalid objections and which are also based on the false premises that JBC was directly in front of JFK, at the same height, and facing straight ahead and also that JBC reacted to being shot at a different time than JFK.
To the best of my knowledge, there has never been a court case where Myers' 3D virtual recreation of the shooting would be relevant. The same could be said of the Knott Lab reconstruction of the shooting. Do you know of such a case?

For what it's worth, Dale Myers did win an Emmy for his work on ABC's documentary which aired around the 40th anniversary of the JFKA.