McLaren + Alonso + Renault = The end of McLaren F1 Honda will not let McLaren die. Renault WILL. The grid penalty era is coming to an end -- MAINLY because of Honda. So, why not take advantage of it?
Expecting a better future with Honda is like a husband still believing that his wife who cheated on him repeated times will become faithful in future!
So seems likely that Alonso will stay with McLaren again for 2018,although he is the last piece in the jigsaw after the Renault/Toro Rosso/Honda announcements yesterday. Zak Brown said they will get their commercial guys to arrange some sponsorship..so expect a lot of haggling regarding Alonso's salary! Flavio will be in his element .