When I was learning how to chamber 10 years ago, I got information from:
1) Mike Bryant's site
http://www.bryantcustom.com/articles/rebarrel.htm
2) A Staff gunsmith at brownells who told me I didn't need a rougher and how to do the arithmetic to know when the chamber is deep enough.
3) Ed Shilen's drill, boring bar, reamer technique I have added doing that in stages, so the pilot is always engaged.
4) Roy Bertalleto in Feb 2000 posted a picture for me of a lathe spider on yahoo gunsmith
http://public.fotki.com/Rbertalotto/machine_tool/shop-pictures/p1010005.html
http://sports.groups.yahoo.com/group/Gunsmithing/message/818
5) At the Puyallup gunshow in 2003, Brett Evans (a gunsmith and benchrest competitor), said I need to put a piece of copper wire [gimbal] around the barrel in the 4 jaw so the spider makes the barrel pivot and not just bend.
6) Daniel Cowen of Renton says he uses a Bushnell collimator bore sighter spud to dial in the spider in a steady rest, when a pin gauge will not reach, because there is already a chamber there.
7) Randy Ketchum of Lynnwood Guns and Ammo, told me he grinds a spud on the tool post grinder to within .0002" of the bore, so he use two test indicators on the spud to dial in the barrel near the chamber. He said all barrels are bent with a spine and just pay attention to the bore near the chamber. He said he pushed the reamer with the tailstock and countered the torque with a tap handle in a piece of shotgun barrel. The shotgun barrel runs stiffly along the ways, so it does not chatter, but he lifts the barrel off the ways with his finger to feel the torque is not too much. He pulls the reamer out every ~ .050", scrubs the reamer off in gas mixed with oil, slathers the reamer with cutting oil, and puts it back in.

What does it all mean?
The short steel rod or tube from the wrench on the reamer to the ways is so stiff, it that were the floppiest part of an oscillation loop, the chatter might be too high frequency to hear.