Comment 20 for bug 1208875

I've pushed to working a branch called user/gmcharlt/lp1208875_revised_implementation that does some surgery. From the commit message:

    This patch removes the proposed custom methods for extracting
    title, author, and record format in favor of tweaking
    ->fetch_user_circ_history to invoke unapi.bre and adjusting
    the template to use get_marc_attrs. Also, nowadays
    ->fetch_user_circ_history can flesh what we need it to without
    having to rely on the existance of an action.circulation row,
    which won't be present if the circ was aged but was otherwise
    retained in the user circ history.

    The result is slower than the previous approach, but still
    retains the core idea of getting A/T out of the equation, and remains
    much faster than the A/T approach.

    Dropping use of unapi.bre would speed things up a bit more, as it
    was added only to match the addition of the record format column
    in the CSV output. Drop the column, and we no longer need to worry
    about MVFs.

    There would also be opportunities to improve caching further. Bib
    display fields, when it comes, will likely help even more, as it
    would mean being able to drop a lot of the XML parsing currently used.

    This patch also adjusts misc_util.tt2 so that including it doesn't
    result in an unwanted blank line.

Removing signoff tag and asking Jason S for feedback; if we come to consensus on this approach, I can clean up the branch further.