How can I loot the bones from St. Eadric's tomb without being detected?

I'll have to do some testing to pinpoint the exact time, but there is a certain time during the day when that room is only occupied by one person. That one person is more focused on sweeping the floor than he is at paying attention to the tomb, making it extremely easy to loot the bones.

Update

After doing some extensive testing (read: standing around), I came up with the following results:

• 11:30 AM - 12:04 PM - Empty
• 12:05 PM - 2:04 PM - One man praying
• 2:05 PM - 5:00 PM - Empty

I would do more testing, but I figured a ~5 hour window is ample time to steal everything you'd need and more from St. Eadric's tomb.

At different times of day, the monks do different things. For instance, when I stole the bones, I stood on the other side of the casket. The monk on the left was apparently on a break, so he wasn't even there. Even though I was in full view of the monk on the right, after crouching for about 60 seconds, his awareness started to drop off to zero of its own accord.

The monk in the center was actually the trickiest, as even though I was behind him, I was apparently too close. After a couple of minutes, he moved out from behind the pulpit and into the room. His awareness then dropped, and I could loot the bones at my leisure.

Go there around 4PM. There's only one guy sweeping the floor, you can steal the whole place.