I'm not sure the Tory party has got itself in to a state lately. I think Theresa May did that with her election call in 2017, her awful campaign, her awful manifesto which led to her loss of 17 MPs.
They had a small majority before then, but also had DUP support, so there really was little risk of the Lancaster House speech not getting through.
Her bad judgement gave the rebels such as Grieve, Allen, Wollaston and Soubry who had endorsed Brexit pre election, the power to influence and shape policy, aided and abetted by such as Hammond, Clark, Gauke, Liddington and Rudd in Cabinet.
Now the Tory party is probably more united and clear than it has been for 2 decades.
It just doesn't have the numbers in the Commons.