Your correspondent is right about the 125 being mainly bad driving. But poor, nonexistent policing is also an issue. They know there is no-one looking.
But it is not the only main road where there are immense problems. I have to use the IC1. My wife will not drive on it, after being almost killed by a heavy goods vehicle driven illegally. I would need the whole of this paper to recall the appalling driving, so here are just two examples:
1) Being overtaken by a large HGV, driving at over 90kph when the limit is 90kph
2) Being overtaken at over 90kph by a car driving on the hard shoulder.
The GNR, as always at the same spot outside Messines, with five new Brigada de Trânsito cars parked while officers stopped people for papers; never looking at tyres, faulty lights etc. Until the roads are policed properly, there will be no improvement in driving.
As to the 125, the road certainly needs work; it is a mess. Some improvements could be: the road downgraded to “acesso local”, removal of distance signs (Faro-Portimão) to be replaced by local ones and, of course, the removal of the tolls on the A22 so it is allowed to do what it was built for – be a main east-to-west through route for the Algarve/Spain.