yes, its legitimate for the Palestinians to do take this approach, to maneuver the situation to their advantage. Similarly, its legitimate for Israel to keep reminding everyone that PA is not entering the negotiations in good faith. These type of reports/statements that keep popping up are part if Israel's program to maneuver the situation to its advantage, which is fair game. When the negotiations fail, they will be able to say that this US administration is the toughest on Israel in a long time, that Obama has repeatedly embarrassed Bibi, that there was a freeze on settlements (and jerusalem, de facto) and that the PA still did not enter negotiations with a genuine desire to negotiate! This will allow Israel to repeat the line about "the Pals not missing an opportunity," and to be fair, they'll kinda have a point.
First refugees travelling on Hungarian bus arrive at Austrian border (Reuters)