Yes relations between Russia and Poland would become less strained if Polish people would accept that what appears to them to be deep anti-Polish sentiment is merely light jabbing and teasing by the Russian people. The Polish people need to let go of the past, and their future will be better.
Russia first subjugated Poland in 1795, a reign lasting for 123 years until the end of World War I. In World War II, they invaded Poland with the Nazis, and kept controlling Poland until 1989 (with a brief interregnum in which the Nazis invaded Russia and ruled Poland, which isn't much better). In the two centuries between 1795 and 1989, Poland has been independent from Russia for only two decades. That isn't light jabbing and teasing; that is a history of subjugation and oppression spanning centuries. Since an expansionist and militaristic Tsarist Russia under Catherine II invaded Poland, and since an expansionist and militaristic Soviet Russia under Josef Stalin invaded Poland, it would only make sense that Poland would fear that an expansionist and militaristic Russia under Vladimir Putin would invade Poland. And that is no laughing matter.
No, relations between Russia and Poland would not become less strained if Polish people would accept that what appears to them to be deep anti-Polish sentiment is merely light jabbing and teasing by the Russian people, because we all know that the Russians are serious in their jokes. The Polish people shouldn't have to pretend that it's light teasing when we all know that it's not.
As much as i love the idea of Putin and Obama putting whoopee cushions under each chairs at the UN, I don't think that ascribing "just kidding" to any nations words and actions is a safe or sane policy. They just aren't cool like that, there is a lot of history and bad blood in the region, and sentiments like that should be treated seriously.
I do not believe relations between Russian and Poland would improve if Polish people were force to see the anti-Polish sentiment they are subjected to, as good fun for the Russian people. This sounds like a pretty bad argument in that it upholds racism and does nothing to suggest a way to fix the problem.
The relation between the Russians and the Polish goes a lot deeper than just light teasing by the Russians. There have been tensions between these two nations for a long time. I think people should stop focusing on their differences so much, because it causes nothing but problems like we see here.