Implode when one stave has 8va----- and the other doesn't

1. Create a score with two staves.
2. Add notes to a bar in each stave.
3. In top stave, mark whole bar 8va alta
4. Select both staves
5. Choose Tools | Implode

The resulting stave is confused, with one voice requiring the 8va and the other not.
I think it would be best (in the case where two staves have different 8va/15va settings) to choose whether the combined parts should or should not use 8va, then write the parts up/down an octave as necessary to represent the same pitch.