In early 1942 the STAVKA was faced with a strategic conundrum; how to continue to exploit it's victories from the previous winter of campaigning, while at the same time adsorbing and defeating the next German blow. Stalin believed that Mosckw would remain the main German target, and thus focused most resources to defending it. At the same time he ordered limited offensive in the south to distract German reserves and throw them off balance.
As it turned out, the main German offensive effort was in southern Russia. The Red Army's limited offensive were destroyed, with 500,000 men lost. These disasters destabilized an already weak southern front which, with no large reserves, was subsequently shattered.
So, what would be the result of Stalin concentrating along the southern direction, and launching limited offensives in the center?