No, JF did sometimes go over to the Halls' apartment for dinner and they would sometimes work on lines. I don't know if she was chopping veg and spouting DS dialogue while JF was reading and sometimes prompting her at the table, or if the read-throughs happened after dinner.
It's been reported in a couple of places, but I think Matt Hall wrote about it in one of his blog entries:
http://msbhall.wordpress.com/A number of the Shadows players used to have dinner at Grayson and Sam's. When Nancy Barrett was asked for memories about Grayson on one occasion, I think the first words out of her mouth were: "She was a fabulous cook."
G.