re-arrange some of the method preamble
<tobyink> stevan: it appears binding to BEFORE on store_data_in_slot_for doesn't allow you to change $data.
<stevan> tobyink: hmm, one sec
<tobyink> Would it be possible to pass \$data to the observer instead of $data?
<stevan> tobyink: yes, and actually I think that is the more correct approach anyway
<stevan> gimme a sec and I will commit it