You know when people aren't really trying to solve a problem, and are just trying to defend and justify their position, when they suddenly start caring deeply about tangential things they wouldn't normally care about much but which support their position.
e.g. I don't believe that the PDCMG and supporters have always had a deep-seated and religious conviction about the critical importance of never, ever causing any alteration of any kind within the boundary of a scheduled monument without permission. Equally I don't believe the 'other side' (whoever they are) care nothing for history and are totally fine with causing damage to scheduled monuments...
Any damage to a scheduled monument, given it was discovered from underneath, was surely accidental... one could argue it was careless, but it was hardly a brazen act of criminality.
The BCA would be wrong to take sides. They have, very wisely, called for restraint. It would be wrong of them to issue a condemnation of illegal acts in this case because that would be taking sides. While they can, should and have made reasonable suggestions which will benefit caving and cavers (i.e. holding back from using the Twll Du entrance until the situation is clearer), they are not the police. Policing cavers is not a role they, or any other caving body, should take, and only the most egregious of acts against caves or caving should result in membership cancellation (and nothing else) - certainly not a disagreement over access where there is not consensus.