John,

I have had experience with this type of component installation and it was not
a happy situation.  You can probably not find any documentation concerning
this as it leads to difficulties especially if rework is involved.  As there
is no solder fillet on or lead extending from the secondary side, heat
transfer is only capable through the tinning of the pad.  As this is minimum,
heat transfer is poor to melt the solder connection.  Depending on the
technician, some will attempt to either increase the temperature, apply
pressure or both which usually resulting in damage.  In the event of any
required component replacement, as a lead does not extend out the secondary
side, besides the poor capability of heat transfer to melt the solder, the
lead can not be moved in the desoldering process usually resulting in a
"sweat" connection (the lead still being soldered to the plated thru hole
from the tinning on the lead and plated thru hole).  Upon attempt of removal
of this component, damage to the plated thru hole is probable.  This
possibility is amplified depending on the lead to hole clearance. All in all,
this type of component installation in my opinion is not suggested.

Marshall Canaday
Applications Engineer / Training Specialist
Pace Incorporated
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301-490-9860