question about the shoe game?

i was fooling around with bjrm and punched in a 1-4 spread black on a 6 deck game. wong in at +2(1.2% edge)using ubz2,s17 das 4.5/6 and came up with 41.00 per 100.how is that possible.i know the shoe game sucks but could it really be that bad.did i screw up the sim?