Lou seems convinced that it's always better to use a LHP against LHB and a RHP ve RHB. The truth is that many Cubs players do not perform according to the book. Let's take a look at some of those guys and see what their numbers are.
Gregg vs RHB .858 OPS in 127 PA sOPS+ 133 vs LHB .578 OPS in 107 PA sOPS+ 48
Marmol vs RHB .701 OPS in 133 PA sOPS+ 100 vs LHB .545 OPS in 116 PA sOPS+ 46
Heilman vs RHB .817 OPS in 140 PA sOPS+ 125 vs LHB .760 OPS in 102 PA sOPS+ 98
Guzman vs RHB .565 OPS in 115 PA sOPS+ 56 vs LHB .676 OPS in 77 PA sOPS+ 73
We can all see that only Guzman fits the mold of using a righty-righty matchup. Clearly the other 3 are considerably better against LHB. When we dig down to the rest of the bullpen we also have some striking numbers.
Samardzija vs RHB .936 OPS sOPS+ 156 vs LHB .896 OPS sOPS+ 133
Marshall vs RHB .808 OPS sOPS+ 107 vs LHB .620 OPS sOPS+ 76
Grabow vs RHB .689 OPS sOPS+ 80 vs LHB .712 OPS sOPS+ 104
Of the remaining bullpen only Marshall follows the script. Samardzjia shows no evidence that he can get either RH or LH out. It begs the question to ask why he isn't at AA learning how to pitch. As for the disparity between perception versus reality in our pen, I would hope that Lou one day takes into accout what our guys are doing rather than what he wants them to do.