হাওড়া - বর্দ্ধমান কর্ড লাইনে যান, 130 কিমি বেগে ট্রেন যাওয়াও কালবৈশাখী ঝড়ের থেকে ভয়ঙ্কর! - Jishnu Thakur

I believe the 632 km is the track kilometer and not the route kilometer. Only the HUP-DMM and KPN-JTJ sections in SWR are the electrified sections outside Karnataka. The total electrified track kilometer within KA does come out to be a little more than 600km (Excluding loop lines at stations).
Most of these developments are usually capital centric. Bangalore's location and the lack of any trunk routes in KA partly played spoilsport in electrification of the routes here. AP indirectly benefited from lying on the MAS-HWH and MAS-NDLS trunk routes. Indeed, other than these two trunk routes (and the stretch to Hyderabad), the rest of AP and Telangana are either still un-electrified or were electrified only in...
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the last few years (RU-GTL in 2014, GTL Wadi in 2017, GY-DMM in 2016 and GTL-GNT going on) and most of these routes are neglected by the zonal railways. Kerala's geography means that anything planned to benefit TVC would end up serving more than half of the state as well. With Bangalore and Mysore being very easily accessible from the trunk route on the JTJ side, all resources were put only into this connection and the rest were neglected.