Sergeant Hill managed seemingly without much effort to get his head and most of his upper torso out the window, so why would the svelte Oswald have any trouble poking his head out and don't forget that Brennan testified that Oswald was sitting sideways on the window sill?
That anyone would argue whether or not it's possible to lean out of a window and look down into the street is f"^king ridiculous.
Of course Oswald in the Sniper's Nest could look down into the street and maybe he could discern the movements of Norman and Jarman out of the dozens of people milling around down there. But to then spin the yarn that Oswald could tell Norman and Jarman were walking around to the back of the building and were going to enter through the loading dock entrance is worthy of a Ford or a Cakebread and I'm surprised your not a little embarrassed by it.
Obviously, Oswald's supposed reporting of seeing Norman and Jarman entering the TSBD, and this actually happening, is a problem for the LN narrative but weaving such a weak fable is not helpful.
Btw I have publicly speculated for a number of years that Bonnie Ray while looking for his companions was at some stage standing with Oswald in the Sniper's nest. And this undesired link with Oswald created some discrepancies in the recollections from the three black men in the windows directly below.
One of the most striking features of this case are the lies of the 6th floor crew and other TSBD employees surrounding their movements at the time of the assassination - Williams, Norman, Jarman, Shelley, Lovelady, Givens and Dougherty all lie. It's a truly remarkable thing.
Each man lies for his own, very different reasons and it is possible to discern a pattern in the lying.
No-one lies more than Bonnie Ray Williams. He lies about every single aspect of his time on the 6th floor prior to the assassination and I believe he drags Norman and Jarman into his lies to cover for him (unsuccessfully) with the authorities. Williams does everything in his power to distance himself from the Sniper's Nest at the time of the assassination
I also believe Williams encounters the assassin in the Sniper's Nest and this is the reason for all the lying.