Flight path dictated by pressure change caused by altitude.
You forgot about stages 2 & 3. The graph is for Stage 1 only.
No I didn't . Stage 1 rockets can only get so high as their efficiency at producing thrust decreases markedly with altitude .
I'm not sure where you learned that. The thrust is constant, not diminishing, as the rocket gains speed as it becomes lighter due to burned off fuel. Burn time, about 2.5 mins before cut-off and jettison.
Stage two rockets have smaller nozzles with a decrease in area that allows more thrust to be produced as air pressure declines - same for stage 3 .All explained to us in physic class and believed by all.
Of course factoring in the rocket is now much lighter all in an effort to get to escape velocity, I think around 25k mph.
Of course perceptions changed once I encountered Joules Law.
The operative word being 'I'. Once
you encountered Joules Law you dispensed with the rest of physics as we know and use it. I don't think you're in a position to do so based upon
your encounter.
If you look at stages 2 & 3 in that link you will see that they are based on the premise of "no gravity" which renders them entirely fictional under what passes for mainstream science . Which is why I ignored them.
Yes and if you read further the author, as a thought experiment, by removing gravity, gets the lunar module to the moon in hours instead of the reality of days. You can find the actual data all over the web, thrust, velocity, weight, time, anything you want. Dig a little deeper and you'll find that your
encounter is irrelevant here.