It may depend on the traffic
Hmmmm, good question.
The hotel seems to have a fair number of people on the patio every time I go by. I think some of the people just go for the bar and are not actually staying at the hotel itself. That may help gentlemen to come and go with a small chance of getting noticed.
I myself have only been in the lobby and did not enter the area with the rooms. While I was there the elevator was temporarily out of service and it seems a rather small elevator over all. The whole place has a small intimate feel. I imagine you do not get a lot of traffic in the hallways since you can only put so many rooms on a floor with a smaller hotel - that would certainly add to the discretion.
To be honest, I think one might be able to get away with it as long as the SP does not have TOO many people coming in and out. 3-4 people throughout the course of a day would probably go unnoticed.
I think the location of exits and entrances would be a big factor in that. To be honest I only saw the one door off of Sherbourne, and it leads directly to the lobby.
