The existing routing of those holes has one and it's in the middle of the 4th hole. I believe they are worthwhile if the green site that follows is exceptional and the blind shot manages to make the rest of the routing work.
Merion actually has quite a few blind tee shots when you think about it. 4, 11, 18. The landing area on 6, 7 and 8 can also be blind or partially obscured, depending on where exactly you hit it.
4 and 18 were two of my favorite tee shots on the course. Blind tee shots have a number of good points imo:
- there is the thrill of hitting over something.
- the shots are played closer to the ground with more roll. I see little thrill in repeatedly watching drives from elevated tees drop softly to earth.
- they accentuate the contours or a property. Especially on flat sites they can make a site seem more undulating.
Of course, they work best on sites with wide fairways and thin rough, which isn't Merion.