The BFH & BFS have been used to perform many delicate operations in my workshop,quite often in conjunction with each other !.I have found that used with moderate doses of cursing they are sometimes the only tools capable of solving the problem at hand.And if by chance the part being massaged should shatter or behave in some other totally unexpected way that defies all of the laws pertaining to physics then owing to their larger than needed size they are easily located by dividing the dent in the opposing wall of the workshops diameter by the distance covered and subtracting from this the force with which they were thrown multiplied by the price of the replacement part.This will give you an approximate distance in meters from the point of origin but does not take into account any deflection that may be caused by the gravitational pull of any expensive or delicate nearby machinery which is directly proportional to its replacment price.
Did that make it any clearer Antti ??
Merry Christmas and a happy new year all Jay.
)