I've been following this restoration project ever since it was discussed and John Colligan was chosen to do it. Personally I am very impressed based simply on the photographs (nearly 100) that they've sent me as it progressed through completion.
They laid out a drawing of the original course over the aerial that is shown on here in Nicholas' posting. By doing this it enabled them to restore many of the original features on about 15 of the holes. Unfortunately the highway that borders the upper right corner is located on the site of three of the original holes. In fact there is a green site directly across the upper end of the road from the course that is in a small public park. This had obvious effects on just how much could be restored and especially on how many of the original angles and hazards could be preserved; still, from what the photos show against the original plans and old photos from Tilly's day, it appears that they have done a remarkable job. I will try to post some photographs to show this.
Among the things brought back is a number of square greens, just as they were originally designed! The restoring of the creek that wandered through the site and was dried up. This was and is once again an important feature on a good number of the holes. They even dug out and rebuilt original stone bridges that will once again be used.
Most important of all was their approach toward the budget. They explained to each contractor bidding that the cost was fixed in stone and that there would be NO "EXTRAS" so they should bid accordingly. The project came in under budget, on time and I believe it will be very well-received by all. I am hoping to be there in January to see it for myself.
Tom Doak, you asked "Did Tillinghast build rectangular tees?" Yes he did, but he by no means did this as a standard. For example, he preferred tees on one-shotters to be as wide as possible and also at an angle to the green site so that the shot angles and hole distance could vary from day-to-day. This would also allow for variations in wind to be accounted for fairly.
I think what is meant here when they speak of them being rebuilt "along geometric lines" is that the tees seem to be a bit wider than usual so that variability of marker location can be more than simply front-to-back, but a bit side-to-side as well. I will see if I can post some of these photos as well.
You also mentioned that you were, "surprised to hear that "Tillie" would have had simple flat-bottomed bunkers with grass faces."
Frankly, I am not surprised to hear someone say this. I have spoken to many architects who have told me that a true Tillinghast bunker has flashed faces and others who say the opposite. Others who say they were flat-bottomed while others proclaimed them to be massive and deep. They are all correct, yet at the same time, mistaken.
Tilly had an interesting "style" when it came to bunker design... he had none. By that I mean that as often as he would design a bunker deep with a flashed-face and filled with bays, capes and fingers, he would also do them with grass faces and flat bottoms or ovoid without much detail and depth. He quite often designed bunkers with remarkably different features not only on the same course, but even on the same hole.
Recently I spoke with an architect who wanted to know whether Tilly employed sand-faced bunkers on a particular site in its design or if they were flat-bottomed with grass faces. He cited an example of Winged Foot and said that he had seen photos from the '20's where the bunkers had grass faces. I emailed him two photos to answer. The first is one of the 18th green taken for the 1929 Open. One can clearly see the left FRONT bunker having a grass-face that comes down about 75% of it with the bottom being flat and somewhat narrow. The other was a photo taken of Bobby Jones playing out of one of the BACK left bunkers on this same hole during this same championship. It is quite clear that both back bunkers have flashed-sand faces and are large.
Two totally different bunker styles just 50 or so feet apart.
Why did Tilly do this? What made Tilly decide to use various bunker styles in this manner? The answer lay in two things. How he viewed the play into the green and the timeframe when the course was deigned.
The most important aspect of any Tillinghast design is the green entrances. Tilly wrote about this numerous times. He believed in designing hazards that would play as true hazards and punish the poor play, but to do so in as fair a manner as possible. What I mean by this is that he designed his holes to reward shots placed in specific locations. The reward would be a preferred angle into the green from the best of lies. Many of these were close by fairway hazards and so risk/reward is magnified.
Now many of these preferred lies would then require shots played with clubs that would cause either a low or high trajectory. With this in mind, he would often times, especially in the 1911-1918 era, design greenside bunkers with grass faces so that shots into them would not bury in the face at extreme angles to the player, but would either bounce of it and down into the sand or get stuck in the rough grass. In either case it would have been punishing but fair in his mind.
From the late teens onward, with equipment advances and golf courses being designed with much greater length, he saw that play then and in the future would allow for shots hit into greens to arrive from greater heights and that play from bunkers was becoming far easier for all. He then began to more predominately use sand-faced bunkers that were deep, irregular as well as narrow in areas that were flat. These narrow flat areas was one of the commonalities in his design philosophy throughout his career. In his mind a big bunker with gentle slopes was far easier and less punishing of the poor play than one that was large, deep and afforded few good stances. It is for that reason that he used fingers, bays, etc...
In restoring a Tilly bunker than, the shape is designed in direct relation to the angle of play into it from the preferred lies.
In the case of Brackenridge Park, a pretty early Tilly design, many, though not all, of the bunkers were designed with grass faces and flat bottoms.