What you write makes sense from the mechanistic point of view.
Almost every vehicle - by design - has the tendency to overshoot. That is the 'ghost point' I described. I can't recall the exact numbers, but it should be in the range of 1-1.5 meters for most mediums. On average, that is. Shots might still be shorter than that. So the best option is to aim those 1-1.5 meters short of the squad center. This will maximize your chance of dealing maximum damage.
I just doubt that it is really worth it with the exception of a few vehicles like the Brummbar and maybe heavies. 99% of players (myself included) don't have the micro to max out the damage of a normal medium tank. I am better off investing that elsewhere, capping a point or building cover etc. The tank will find a decent solution on autofire. Those additional 5% damage or what it will be does not compensate me forgetting squads that I could micro instead.
I don't see a reason why the Sherman should be special in its mechanics compared with other mediums. I assume this is probably an observation bias that stems from the HE shell. I think you'd need to sink in tons of hours to >really< get the correct feeling of manual targeting being that much better than autotargeting with medium tanks. The difference is not that large to begin with, and everything becomes even more noisy with non flat terrain and rubble/world objects around, as you already mentioned.
 
	 
        
 
  
  
  
				 
			
 
					 
					 
					 
					 
					 
					 
					 
						 
						 
						 
						 
						 Relic Entertainment
						 Relic Entertainment
					 cblanco ★
									cblanco ★								 보드카 중대
									보드카 중대								 VonManteuffel
									VonManteuffel								 Heartless Jäger
									Heartless Jäger								 
											 
								