Re: How exactly did Clara "save" the Doctor.
The problem with explaining things, is that you will likely dissapoint some or all of your aduaince. So sometimes it's best not to give an explation at all. Simply that somehow she interfers with the GI.
On the continent of wild endeavour in the mountains of solace and solitude there stood the citadel of the time lords, the oldest and most mighty race in the universe looking down on the galaxies below sworn never to interfere only to watch.