In a normal parliament yes. But the Sejm is full of venomous PO and Petru types not interested in anything but PiS-bashing.
The thing is it has always been so in Poland since 1989. Politics in Poland equaled hate on the competing party.
During the times when PO was governing it got more or less stable. I wouldn't say that the reign (I am not sure if it's a good word to describe the way of governing in a democratic republic, but I cannot find any better in English) of PO was really good. But it also wasn't bad, and comparing now Poland with other post-communist EU countries (not counting the former DDR, it's a totally different story) - it seems to be the most developed one. Really many things changed to better. Some people compare their reign to Edward Gierek's reign from the 1970's, with a lot of investment and modernisation, which, however, ended with bankrupcy of the country and a crysis. But I don't feel we have a crysis now, just on the contrary - our economical situation seems to be very good.
There was also many evil things in PO, but they are not unpresent in PiS. That's why PO failed. Some scandals came to light, Nowoczesna appeared, the electorate got divided, also some people saw hope in PiS, which advertised themselves as a modern party, changed from what it was 8 years before (which turned out to be nothing of the truth).
Anyway, during the PO reign - maybe because it lasted two terms - this hate between the parties wasn't felt so much. But after the victory of PiS, this wild hate returned. On both sides. Both PO and PiS.