I have always had difficulty accepting this thesis, and a recent event convinces me that it is false.
Sky News.
An extension of grammar schools looks to be her first big policy announcement as PM, and while she will pitch it as extending more opportunity to more children, there is a healthy dose of political calculation in her enthusiasm for their reintroduction.
May is evidently at ease with extremely reactionary policies. She likes them, and she is in sympathy with the minds who propose them. She wants Brexit to succeed, and she wants its supporters to vote for her in 2020: she is now offering them "good" schools, where they will secure selective education for their children
If she is making a mess of Brexit, it's not because she
wants it to fail, but because it is intrinsically intractable, and may well fail of its own accord despite May's best efforts to make it succeed.