True, 6th Army was weak. But it wasn't that weak, else it wouldn't have taken the Russians months of bitter fighting and horrendous losses to finally crush it. 6th Army, though surrounded and low on supplies, was still able to put up a hell of a fight for quite a while.
I can only conclude the failure to attempt an immediate breakout was a catastrophic strategic blunder. Almost certainly the Germans would have been better off had they done so.
If a good portion of 6th Army had managed to extricate itself, would it have altered the course of the war? Probably not but it's hard to say. It most certainly would have led to a different end state at the conclusion of the summer campaign, so the Kursk salient might never have come into existence.
More than likely the survival of 6th Army would have made the conflict take another 6-12 months to play out on the Eastern Front, and not doubt added to overall carnage. Interestingly, prolonging the conflict in Europe could have resulted in Germany being the target of the A-bomb instead of Japan. Who knows how that might have altered history. Also, 6th Army's survival on the Eastern Front probably would have meant the Russians would never had had the opportunity to occupy Poland, Hungary, half of Germany, etc.
Initial comparison of forces 13th September 1942:
Units either attacking Stalingrad or Defending Stalingrad directly).
6th Army:
XIV Panzer Korps (elements 16th Pz Div 3rd & 60th Motorized Divisions, all along the North edge of the Orlovka pocket and along the Volga west bank in the Spatakovka region).
LI Army Korp Gruppe Stahel (Gorodische area), 295th Infanterie Div (Razgulaevka, objective Hill 102.2), 71st Infanterie Div (Tsaritsa gorge sector, objective central Stalingrad).
Fourth Panzer Army:
XLVIII Pz Korps 24th Pz Div 19 Operational Panzers(Tsaritsa river line), 94th Infanterie Div (Sadovaia station, objective Minina Suburb), 29th Motorized Div 20 x Panzers(Minina area, objective Kuprosnoe/Volga river bank).
Total fighting force available 80,00 men and roughly 100-150 AFV (Panzer & Stug).
62nd Army:
Remnants 33rd Guards,124th/149th/115th Rifle Brigades & 282nd NKVD Rifle Regt & 724th Rifle Regiment(196th Rifle Div) (Northern flank Orlovka Salient)
2nd Motorized Brigade (western nose of Orlovka Salient).
6th Guards Tank brigade (15 x T34, 4 x T-70), remnants 87th Rifle Div, 189th Tank brigade (8 x T34, 6 x T-70),38th Motorized brigade,remnats 112th Rifle div, elements 42nd Rifle brigade, 1 Regiment 244th Rifle Div (south side of Orlovka salient down the western side of Stalingrad to northern bank Tsaritsa gorge).
2 x Regiments 244th Rifle Div, 10th Rifle brigade, 6th Tank brigade (18 x T34 ), 131st rifle div (remnants in reserve), 133rd Tank brigade (23 KV-1) & 271st NKVD Rifle Regiment (holding from south side Tsaritsa Gorge all the way down past the MTS and Barracks hill, west of Minina suburb and northern edge of Kuprosnoe suburb.)
Remnants 35th Guards Rifle division (Kuprosnoe and Electro Furnacemill).
Total Fighting force available as far as records show 90,000 men and roughly 150 Tanks (although at least 18 of these were immobile and dug in in the Minina area).
As can be seen, 6th army was attacking into a major Urban area with less men and strength than the defender, as we all know, in rural you are looking for at least 3 to 1 odds in the attackers favour, this is when attacking into Urban, so 6th army was stacking the odds against itself from the off.
As to a withdrawal in November, possible as said, but 6th army would of been in no fit state for a very long time, so even IF it did manage to break out, it would of been of very little use if any to Heers Gruppe Sud.
All of this is clearly 'what if' IMHO, I still think if they had conducted a proper withdrawal in late October/Early November the army may still of been able to save itself to a certain degree, Zhukov may well of tried to stall/stop this pull back. Fighting would of been very, very heavy and losses again would of dealt the 6th a major blow, but the army would of still been in the field and usable, even if only to hold a sector and free up better equipped and manned units to fight the Russian attacks.
But yes, in a nut shell, 6th army was between a rock and a hard place manpower wise even before they attacked into Stalingrad proper, that they managed to rest as much as they did from the Russians with what they had on hand is if you ask me nothing but close to remarkable, also, that the Russians managed to hold what they did with what they had near the end is even more remarkable.
Will we ever see another battle like the 'Grad' ever again? who know's, I doubt it (and that includes Alleppo before anyone cries that name out), but it has and will continue to fascinate people and provide a source of ASL material for years to come.
all the best
Perry