Syriza supporter Marine Le Pen will be unhappy.
The most popular party for 18-24-year-olds now is the far right Golden Dawn, while Syriza languishes in fourth place, data by the pollster Alco show.
Thus, you give the people, including the youth, an "extreme" far-right alternative, and, given the proper circumstances, they'll flock to it.
Further, in an "open marketplace of ideas" scenario, in which there is no constant state oppression against the "extreme far-right," you won't even need to wait for those "proper circumstances" - support for the "extreme far-right" will be the default position.
At some point, when the mainstreamers fail, hopefully there will be "extremists" to pick up the pieces.