Yes, LHO executed a very good plan.
I created a model of the sniper’s nest and sat in it with a similar sized rifle aiming at targets located at the proper angles. An intentional early first shot makes no sense to me. That’s just one reason I think that an early first shot must have been an accidental discharge.
One aspect that Google Ai mentioned is the offset mounting of the scope. If the offset-to-the-left scope was zeroed-in for 100-feet for the Walker attempt, and remained that way on 11/22/63, then Google AI’s point about the furthest shot point of impact being slightly to the right of the point of aim might be the reason the bullet struck JFK slightly to the right side of the back of his head. I already knew that this is an issue with offset mounting of a scope, but hadn’t applied that knowledge to the JFK assassination until I read that AI point today.
We've had this discussion before. Even if Oswald only had a 5% chance of hitting his target, that's a better chance than if he didn't take the shot at all. He still had the later shots if he missed with that shot.
Oswald set up a very effective perch to fire down Elm St. I think that was his primary plan all along. But as his target approached on Houston St., I would think he would start contemplating whether taking that early shot made sense. He only had a limited amount of time to make the decision. While neither of us can know for sure what Oswald's intention was on the first shot, I can certainly understand why he would decide to take that awkward shot.
I didn't go to the trouble of creating a model of the sniper's nest but I did use a few objects to kinda sorta give me an idea the challenges that first shot would have presented in addition to the angular velocity. I have a Sears Ted Williams Model 53 .30-06 bolt action rifle which is actually a Winchester Model 70 which they slapped the Williams name on it back in the day when Sears hired Ted Williams to endorse their line of hunting and fishing equipment. Sears did that with lots of brand name products that they sold under the Sears name. It has a top mounted scope. I don't know how the trigger pull compares with the Carcano but it seems to me with my rifle, it would take a pretty good jolt for me to accidentally fire the rifle. I would think that if Oswald didn't intend on taking the early shot, there would be no reason for him to move around much. I think it would make more sense to set up in his intended shooting position and begin tracking JFK in his scope as he was passing under the tree. I don't see an early accidental discharge to be likely if he was doing that.
I'm curious as to what the minimum distance setting Oswald's scope allowed. I wonder if it could even be adjusted down to 100 yards. Do you have any information on that?