And here's Jo Walton's contriution - Mary Stewart, 1916-2014: An Appreciation
http://www.tor.com/blogs/2014/05/mar...n-appreciation
{extract}
Some of her romantic novels also edged into fantasy, especially Touch Not
the Cat (1976) which features hereditary telepathy. Many of her other
romance novels used fantastic elements quietly and without any fuss, even
though the books were set in the real world. Best of all these details were
used as if she found the elements of the fantastic exactly as appropriate as
any other elements to insert into the story she was telling. This isn't
uncommon today, when the presence of paranormal romance has encouraged
writers of romance to insert such things, but it was very unusual in her
time and generation. Stewart is also to be commended for how well she dealt
with the fantastic, and how seamlessly she integrated it with everything
else. There's a lot to be learned from her technique there. Being aware that
she would use the fantastic when appropriate made all of her novels more
enjoyable for me—she was prepared to open up the space of possible answers
to mysteries, even where the answers didn't go in that direction.
==
With links to her review of The Ivy Tree (she preferred Nine Coaches
Waiting.)