Like Ereshiy, I spent the evening cutting into an EM bra to move the straps inwards last night. Mine was a foam cup (CHP Brzoskwinka) so I was a little bit hesitant to try to alter the cups themselves.
Instead, I just moved the straps themselves a little bit further into the cup, and then added a small secondary strap attached from the corner of the cups (where the straps used to be) up diagonally to attach to the straps themselves.
The end result is much more supportive (no more collapsing cups or gaping) and for once I managed to execute my alterations neatly enough that it looks like the bra came that way.
CHP Strap WTF - Imgur
Filed under Bra alterations