Well, that is all very good but does not really show my points as wrong.
Your argument was that:
We know exactly the results of retaining McClellan after Antietam. We have the evidence of little mac's generalship and state of mind between the Antietam and his final dismissal, i.e., what did during that time is what he would be doing if his command had been affirmed.
McClellan was a bitter, burnt out shell of the ebullient and confident young general that entered Washing being touted as the 'savior of the Union' . He only wanted out and the only reason he did not resign, was his love and concern for His Army of the Potomac.
He considered he was fighting to sustain a Commander In Chief, he could not trust and an administration he despised, in support of policies he believed was leading the country to destruction.
By the time of his final removal, only a complete overhauls of Lincoln's administration and a major reversal on most of its policies, could have induced McClellan to give any further 'good' service to the Union War effort as then presently constituted. , i.e., as far as Lincoln and his administration was concerned, little mac was gone , and, Good Riddance.
But the thing is, this doesn't really seem to jibe with the actual situation, and in particular the events of the Loudoun Valley campaign. If I may:
17 September: Antietam. McClellan launches 3/4 of his army present on the day on actual attacks, comparable to other Union commanders on the offensive against Lee.
18 September: no major action, comparable to one of the days at Spotsylvania (etc.) where the armies recover from their ordeal.
19-20 September: Lee retires over the Potomac overnight 18-19, McClellan advances at dawn. McClellan sends 6th and 2nd Corps to secure other crossings, 5th Corps crosses at Shepherdstown and is repulsed smartly by a ten-brigade force of Confederate troops. This shows Lee is still able to manoeuvre and fight - he is not a beaten force, and can deploy a force of about 3 Union divisions to resist a crossing (this is what he demonstrated, he still has another ~30 bdes he didn't use there).
Over the next few days, McClellan plans to bridge the Potomac at Harpers Ferry. He intends to let the Potomac rise so he doesn't have to worry about Lee crossing into Maryland, then attack Winchester (and effectively outflank Lee
On 26 September, Halleck says he's worried about a whole other rebel army that might attack Washington, and he's refusing to send previously-agreed reinforcements plus isn't going to approve McClellan's requisitions to bridge the Potomac until McClellan's plans are "agreed upon" (i.e. by him).
In this period McClellan is working on an offensive plan, until Halleck contests it.
From 26 September to 6th October, McClellan has sent his plan to Halleck and Halleck hasn't replied either approving it or disapproving it; Lincoln visits the army on 1st October and sees how poorly supplied it is. (There's a food riot.)
In this period McClellan recorded that he was not under pressure from Lincoln to mount an immediate offensive, and Stoltemyer found confirmatory accounts that supported McClellan's view. There is work that could be done to improve the army's condition and of course those bridges are needed.
On 7th October Halleck orders McClellan to give his plans for an offensive. (That is what the order was. He was directed to cross the Potomac and attack, but the
order was to immediately send
how he was going to do that to Halleck for approval.)
Same day, McClellan sends back his plan for an offensive movement (into the Shenandoah).
Halleck does not reply to this plan. At all. He sends other messages, but he neither approves nor rejects McClellan's plan for an offensive.
From the 7th to the 23rd, the supply crisis in the AoP deepens until it's finally resolved towards the end of the month.
On the 22nd October, McClellan sends a different offensive plan, and
this one Halleck approves late the following day.
McClellan begins his offensive movement on the 24th, throwing a bridge over the Potomac starting on that day and crossing his first troops on the 26th; from that point to McClellan's relief the army is in continuous motion south.
So no, there's basically a period of 50 days from Antietam to McClellan's relief. Of that time, 26 September to 22 October (26 days) is McClellan waiting for Halleck to approve a plan to attack into the Shenandoah (while using the time to rigourously drill his army), and 23 October to 7 November (15 days) is McClellan actively conducting the operations of the Loudoun Valley campaign, moving south on the offensive line Lincoln had asked for (as opposed to the one McClellan had originally preferred and asked for).
There's only a very few days where McClellan isn't either on the offensive or waiting for an approval (or rejection) of
how to go on the offensive.