A barrel bulge is cause for concern and appropriate investigation, but it is not necessarily catistrophic for the barrel. Just as not all skids result in a car crash, still we avoid skids to the extent practical.
Note that words like "soft," "hard," "elastic," and "brittle" are qualitative and not quantative. Steel is not either soft or hard or elastic or brittle. It is some quantative combination of these qualities.
Lets carry the metalurgy a bit further. Stress is the amount of force applied to a piece of steel. Strain is the amount the steel deflects/moves in reaction to stress and stress level is the reaction to a specific amount of strain. Common logic says that a piece of hard steel will have less strain for a given stress level than will a piece of soft steel. In this case, common logic is basically wrong. The hard steel will strain to a greater extent without plastic deformation than will the soft steel; this is why springs are of hard steel. To the point where the soft steel yields, the stress-strain relationship is basically equal between a hard and a soft piece of steel.
In the case of the bulged barrels, it will take a higher stress to increase the bulge (to increase the amount of plastic deformation). The bulge will not grow from normal firing if it is not cracked. Steel work hardens due to strain. In the example of the wire being bent, the strain is fixed by the amount of bending, not by a given stress level.
An overly hard steel may act brittle. That is, it will break at low strain levels. However, this is due to crack initiation at a stress riser, such as a scratch in the surface. As I recall, Browning super barrels are relatively soft. Therefore, I'd expect a wad 'o tabakky lookin' bulge before the bulge cracked. Also, being soft, they are much easier to work down the bulge.
B - not a dumb question, but, obviously, you aren't visualizing the sleeving process as it happens. Note that the sleeve extends full length of the barrel. So, if you did have enough metal to allow rechambering the barrel on the muzzle side of the cut, you would wind up with some mighty short barrels. Say the bulge is 4" in front of the back of the chamber and you had to cut out an inch to eliminate the bulge. You need enough "meat" in the barrel tube starting at the cut to allow chambering. And, you loose 5" of barrel length as you set the barrels back to the chamber face.
