Doing these kind of reckless stunts just to get Sweden to side with Nato was definitely not needed. Sweden was already on Nato's side, and everyone knew that.
I can imagine Sweden's friends in Nato were invited from time to time to practice together. But that doesn't exclude a presence from the Soviet union, and we have actual proof (not just people saying things) that the Soviets were in fact in Swedish waters. Deep within a military protection area in a hard-to-navigate archipelago on top of it, and possibly with nuclear warhead torpedos!
Also when you refer to things such as
> Current Defense Minister Bjoern von Sydow said he was surprised, but added, ``I have no reason to question what a former U.S. defense secretary is saying.″
That just means that he can neither refute nor affirm whatever has been said. Ie, he either knows nothing, or can't say anything. The statement gives no information, except that he was personally surprised. A lot of statements from politicians are like this.
I'm signing off on this now. I don't understand your interest in this topic nor why it's so important for you to show that it wasn't the Soviet union. The Soviet union is gone, but they were a real threat back then.