Marian Wirth allowed me to post his pithy assessment of Grass, hoisted from a comment feed on another website:
Grass was pretty much the last surviving founding father of German post-war literature. He became instantly famous with his debut novel and used the financial independence and the fame to promote authors younger and/or less successful than him, to improve Germany's position in the world and to boost interest in German as a language all over the world.
It still confuses me to hear foreign authors praise Grass - celebrities like Salman Rushdie, who spent the day Grass died defending him on Twitter, as well as national celebrities in, say, Brazil or Nigeria, who tell you how much they adore Grass ever since they read the TIN DRUM as a teenager and I'm always like "WHAT?!" when I hear that because everything about Grass and his most notorious book is so German that I have still trouble believing it even got translated into English.
Bottom line: He was THE most important figure for German literature and one of the leading brand ambassadors for German culture. Even people who disagreed on everything with Grass can't deny that and it drives them crazy, I can tell you.
Grass was a man of many talents. Unfortunately, he got famous for writing novels, his least developed talent.
He was a world class boozer, smoker and dancer.
He was an outstanding sculptor.
He was a phenomenal graphic artist.
He was an efficient SPD canvasser.
He was one of the three leading anti-Semites in Germany, and a decent poet, resulting in the ugliest piece of anti-Semitism published in Germany after the second world war.
His novels are more or less unreadable, since he subscribed to the leading principles of German post-war literature such as the following: avoid direct speech at all cost. Direct speech and dialogue are evil, leave them to the Americans and their movie-script like writing. It's your job to make the readers suffer. Insurmountable blocks of text are your thing. Long winding, meandering sentences filled with German guilt and with guilt to be a human being enjoying life are your profession.
I have read several of his novels, though failed twice to read the TIN DRUM (I'll give it a third try soon). "Too Far Afield" took me over a year to get through. My favorite Grass novel is The Meeting at Telgte.
Politically, he was wrong on everything after 1990. Not only was he wrong on everything, his criticism was always over the top, mean, vile and presented in an apodictic fashion that made it impossible to argue against it. This rant is presented in a similar way to make it more obvious what drove me away from Grass.
So much for an executive summary of what needs to be said about Grass. Vale, rest in peace etc. should still apply, of course.