HI Gary,
Thanks for your kind words about my book.
As regards your question, I always think it is important to remember that separate teeing grounds were not introduced until 1875. Prior to then players just teed up their ball on mounds of sand various distances (from 1-12 club lengths) from the previous hole.
So as regards the 11th, if it was the year 1845 and you went to play the 11th hole (with your feathery), you may have found you were teeing your ball from a position much further to the right than the current 'Championship' tee. So the angle could have been reasonably significantly different, but as Tom mentioned, the elevation would not have been much different (still an uphill shot).
As regards tee shots from the other holes;
13, 14 and 17 have been affected by the new tees. To a large degree this happened when it was decided the right-hand course would become the championship course and these tees were extended back. But the positioning of new bunkers has also impacted the on the tee-shot experience since they use to tee up right next to the old holes. The 14th is an interesting example . In 1875, to avoid the 'beardies' they would have tee up on the green, and had to play either left (down the hole we know as the 5th) or right onto the 14th fairway. The right hand line was a dangerous shot because it was towards the wall (though the wall was not O.B. until 1911). Nowadays, there is only one line off the tee and it is away from the O.B. Wall. So some have argued that the current tee shot is less interesting and challenging that it has been at previous times in the holes history.
Hope that helps.
Scott
PS- for further reading and plans, see pages 90-91 and 140 of my book