The BE, while having some really good people (Rui Tavares and Daniel Oliveira come to mind) is more or less a bunch of trotsquists and stalinists dressed up with some social-democratic slogans. But below that cover they are far-left. In fact their behavior when near power is extremelly sectarian. They broke from their own independent governor in Lisbon by absolutely small reasons. They behave like the owners of the truth and in a coalition would only accept that everything would be done their way (the type of behaviour one would expect from people who believe they are the full owners of truth and reason).
I also don't agree with the classification of CDS as a christian democratic party in the European Sense. They are more like very near-fascistic. The likes of Angela Merkel and JP Balkenende are way to the left of CDS.
In terms of "overton", portuguese politics is more or less like this: CDS EPP (5%) - really UKIP BNP PSD EPP also (30-40%) - Tories PS PES (35-45%) - Right of New labour (though with a good "old labour" group inside) PCP GUE/NGL (5-10%) - Stalinist as described BE GUE/NGE (5-10) - Coalition of left urbanites, lead by Trotskyists (old PSR - Socialist Revolitionary Party - Affiliated with the 4th international) and Stalinists (old UDP - Popular Democratic Union - fans of Albania)
There is also a Libertas party (MMS - Movement for Merit and Society), new one, lots of money, lots of outdoors, but seems to be pooling around rounding error numbers.
The truth is, there is no social democractic or christian democratic party around (in the sense of the german SPD or CDU). But, overton wise, I would say that SPD and CDU would be left of the local PS (PES).
The only lefty thing of Portugal is the pension system and NHS. Gini is a disgrace (worse in western europe), welfare very low, minimum wage barely affords a room in Lisbon (450E a month), power distribution is a disgrace, community involvement unheard off.
While in Spain they seem to talk about the people that make only 1000Euros, here it is common to talk about the 500Euro salaries. If you make rates of GDP/capita and minimum wage, it is appalling. Especially consideing that GDP per capita is already low. The country is poor (for western european standards) and has the worst distribution of wealth. Politics (overton) represents that very well.
Actually I have that problem with the BE. There seem to be several figures that while not as prominent media wise, have some weight inside and still push for those trotskist
I base my relatively good impression on them mostly from the interventions of those you mention, (D.O. and Tavares) but also from João Rodrigues the economist at ladroesdebicicletas.blogspot.com or Pedro Sales, their press guy also present in DO's Blog Arrastao.net.
But these are relatively young elements, and may not yet carry the internal weight that would turn the party to a coherent and sensible leftwing party.
Anyway, i believe they will be the ones to scare the PS from the left, this year.
EU Profiler is an European vote adviser. While for Portugal I got a recomendation of voting BE (I will vote PS), on the European level I was deemed closer to the Dutch PvdA (PES). This I think is a good example of "overton" issues (closer to a marxist party in one country, closer to a social-democratic one in another).
There are 2 new parties, with what seems to be lots of money: MMS and MES (lots of outdoors). I don't know that much about them, but the ammount of money, the aesthetics, the general message doesn't raise cousy feelings at all. MMS seems really, really bad.
Anyway, all of the above are pooling at rounding error levels.
