I am not certain that he is a polemicist.
I do think that he is a fanatical believer in his own position which has coloured his judgement beyond reason and so he writes the irrational stuff that he writes.
No father should have to bury his son - especially one that he must have been immensely proud of - and rightly so - but his ramblings preceded that, so perhaps he can now not let go.
I make no excuse for him - but I do believe that his controversial positioning makes him vulnerable to logical criticism.
His activities during the Falklands were no "braver" than those of many others who received less recognition. I am not saying that he was not "brave" and a "good leader" - but there were many of those in all three Services.
In my opinion, he loses credibility for his own achievements by his continued ramblings.
I do not know - but I doubt that his son would have approved.