by Legio X
This past Saturday I saw LIRR MP-15ac's pulling several TTTX flatcars with new M-7 sets on them eastbound past Richmond Hill team yard. Today I saw 152 pulling a set of M-7's with 167 bringing up the rear. On this move, the M-7's were coupled directly to the MP-15ac's, and thus running directly on the rails. Why would the move on Saturday be done on the TTTX flatcars, and today were already on the rails?