SRR is the gateway of Malabar area , the reason for constructing 7 platform is there only for accommodating interchanging of pax to other direction trains. I'm not telling that NSG 1.2.3 and all. Sabari Exp in an important trains for Malabar area people that is the only reason railway is still doing the reversal there, in spite of all other skips and ZBTT. Im not very clear about railway stn financial category and all, i was a regular traveler of Sabari Exp to CTO from SRR and always seen a lot of people boarding this train and using connecting trains like 16606/16159/56616. Still railway is continuing this reversal is only for supporting a majority of people only else it could have been different.