Despite Boris Johnson I still go to London now again. There’s the odd briefing and brainstorm. Lunch with dad, brighter than me at 90. Cello duets, expletives and venison stew with sis and her three young genii, all brighter than me. And time with Misha, who’s brighter than us all. After an hour with her, I’m armed with phrases for a week and looking forward to living the next 40 years.   Misha lives in a vast and rambling Crouch End maze of kids, headless mannequins, kittens, disco balls, old pulpits, dumb-bells, an enviable collection of coffee tins, the…