...do you think whatever protection you could create would be able to withstand the power of the seventh fonons even if they did go out of control? Fonic artes are weaker within the barrier, so I can't imagine they would be able to do anything too terrible, even if they did.

[Even if they can't test it, so far this sounds like one of the few ideas that actually accounts for all variables. The risk may not outweigh the potential benefits, in his case.]