Frankly, I am a bit surprised that they elected to attempt another 5-day extravaganza. I participated in the one that ran last fall and even with a smaller group size and a somewhat lower price, I think it was difficult to sell. It wasn't obvious until very near the deadline that the trip would run...and that was with operators in both the US and Europe working their respective client lists.
Sixty was too many people IMHO. While the line is wide open most of the time, there were some locations, such as Phantom Curve and Rock Tunnel that were a waste of time because of the large group. In fact, it got dangerous at times, because there were so few good spots to stand, that some people took some serious risks.
One of the reasons that the trip did sell was that the operator offered a "train-only" option....meaning find your own hotel accommodations. I think most of the US patrons took that option, as did I. In the case of the proposed 315/463 trip, a major turn off for me is the thought of spending the night with 80 of my best buddies in the Osier Dining Hall. I suspect I wouldn't sleep a wink in that environment.
Crowd control is another problem. When 80 people pour off a train, if there isn't immediate, strict control, you'll have a free-for-all.
Lastly, 5 days is a long time dealing with 80 people. Most of the folks that I talked to on last year's trip were pretty tired of dealing with it after 3 days.
I think I would have opted for a 2-3 day event, with a smaller crowd.
/Kevin