As Ian says, never go back in there again, or if you do tell him he is talking BS.
SPD are fine, and shimano even do adaptors for SPD now on flat soled shoes.
I use Shimano A600 "ROAD" SPD pedals
http://www.chainreactioncycles.com/shimano-a600-road-pedals/rp-prod74749
and northwave shoes
http://www.chainreactioncycles.com/northwave-striker-carbon-5-mtb-shoes-2013/rp-prod91019
And i use them on road bikes, as do many others.
FWIW SH56 cleats are multi release, and are way easier to clip in and out than SPD SL, Look etc.