thanks acorn

up to a point... thing is, correct me if wrong but:

if you edit inside you only see the object[s] that has the mask[s] applied
if you open the opacity mask you only see the masking object[s]
if you detach the mask you can no longer see through the masked area

which ever way you are doing it you cannot edit the masking shape whilst being able to see what is being revealed/hidden in real time

there is a way round this by detaching the mask and temp given the mask[s] and masked objects[s] transparency, but that in itself can introduce visibility issues and become a tad unwieldly