By Slon-76
You consider, what the situation in 1941-44 differed nothing from a situation at 19-39?
As far as the frontier in the Isthmus goes there was no essential difference between the two periods apart from the exchange of possession of the land twice.
I.e. if Stalin has decided to supply Leningrad through Finland, Finns would not began to interfere? I think, would began. It also refers to "to block".
Stalin did decide to take land from the Finns to safeguard the city. Had there been no Winter War who knows how the events would have unfolded.
Simply Germans did it actively, Finns - is passive. It does not change sense of an event.
How can you say Finns blockaded the city during the war but not during peace ? From the logical POV the Germans attacking from the South is irrelevant.