[According to the CIA World Factbook, in Poland 17,4% of the labour force works in agriculture, for a total of 3 million people. For the EU as a whole, they have 5,6% and a total of 12,6 million. In other words, Poland represents about a quarter of the EU's farming population.]
Now basically there are two scenario's here: On the one hand, it is possible that the Peasant Party minister responsible spoke without fully appreciating what he was doing. After all, it is one thing for countries like the Netherlands and the UK to call for CAP reform, but for Poland to join them is an entirely different matter. Of course, joining them is hardly what he did, but it will be percieved that way all the same. (What he in fact did is demand that all the differences between the EU-15 and the new accession countries be abolished in this area.)
On the other hand, it is also possible that Poland decided it is worth the risk. They may have estimated that the votes for any serious budget cuts on CAP in the 2014-2020 period (which is what we're talking about here) are simply not there, and that there is some kind of deal to be made that benefits the farmers of Poland at the expense of their French counterparts. Part of this calculation may have been the French-German discussion paper on CAP reform published in September, which has a distinct market-oriented flavour. Needless to say, market oriented is not what you want to hear if you're Marek Sawicki. Even if the overall size of the CAP budget is not going to be changed, and if there is to be no national co-payments, Poland would still want to keep competitiveness out of agriculture. Quoth Wikipedia:
Agriculture employs 16.1% of the work force but contributes 3.8% to the gross domestic product (GDP), reflecting relatively low productivity. Unlike the industrial sector, Poland's agricultural sector remained largely in private hands during the decades of communist rule. Most of the former state farms are now leased to farmer tenants. Lack of credit is hampering efforts to sell former state farmland. Currently, Poland's 2 million private farms occupy 90% of all farmland and account for roughly the same percentage of total agricultural production. Farms are small—8 hectares on average—and often fragmented. Farms with an area exceeding 15 ha accounted for 9% of the total number of farms but cover 45% of total agricultural area. Over half of all farm households in Poland produce only for their own needs with little, if any, commercial sales.
Unsurprisingly, what Poland seem to want is as much as possible of a straight per-hectare payment.