I just tried again to mold my favorite formula with the predicted disaster -- air pockets under the lid.  I let it proof standing on end so the air could escape and then must have inverted the top and bottom of a not yet fully proofed dough.  Anyway it would have worked better to let both halves rise where I could see them and just stick them together before baking.  

The mould did separate in the middle by about 3 cm but it is quite a pleasant seam and made it easy to stick a probe thermometer into the loaf.  I could not control the sliding of the top sideways by a centimeter or two.  Remind me to tie a cord around the capsule next time.