Krish:
First of all a long distance train should cater for long distances! In other words a long distance train may cater to an intermediate strech in addition. For example jayanthi janatha is a train which is supposed to cater guntakal ,kadapa ,mantralayam road etc..... in addition to dat it caters Kaniyakumari to trivandrum ,ernakulam etc....
What sort of step motherly treatment do they get? They get a best treatment possible though it may be dumping. The 'perfectly dumped' train is ernad only. People cannot board it at any cost. Parasuram though...
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not at so good timings fro nagercoil it is not so bad either. It is a good intercity from the nagercoil side towards ernakulam,kottayam,etc... madurai division has rameshwaram , tiruchendur,tirunelveli, etc... as better terminals compared to Kaniyakumari and nagercoil to where upon extension of trains they'll lose their share of quota too.
For a long distance train surely an hour of travel is not going to matter at all and always rather than 'shorter distance' , ' shorter time' matters. A simple example is prefering of salem-bangalore via bangarapet than via dharmapuri. Expecting the long distance trains to cater small distances or as intercities is mere absurdity and ridiculousness. In another point of view their so called 'dumping or kerala route' has earned them better connections to kolkata,katra and many places. In their view it has earned them coimbathore, tiruppur, erode connections which they wont get otherwise as shortest route is via dindukkal,namakkal. Through tamilnadu they have thirukkural , Bangalore and the mumbai train. All a place needs is a good train and they need to check the destination and time , not the intermediates! A nagercoil bangalore can cater nagercoil to salem passengers but it should cater nagercoil bangalore primarily. Now the mumbai train via tamilnadu is not a shortest route and shortest is via kerala ! So can we take the train via trivandrum and konkan? Will they agree? Island was from trivandrum and meant for kerala which they had asked for! Now they change their colour!wow! If they can spent extra money on Nagercoil mumbai then why cant on the other trains? Travel Time is just differing by an hour or around! Tirunelveli bilaspur is a proper dumping which is justified, agreed, but even at trivandrum its just a not so bad time! Dibrugarh train will cover the southern capital and timings Show that its not bad enough to be diverted via tamil nadu.
If punalur and nagercoil are exchanged
This will result in maximum extension of sengottai trains to Kollam or trivandrum! That means pothigai and madurai passengers will come and dats all! Madurai division has better terminals as destinations and Kaniyakumari will not or has no more need for a train than one or two short distance trains! The existing services will continue or if withdrawn naturally they'll lose existing connections only! The trivandrum division may dump or may be serving kerala but indirectly Kaniyakumari has only benefits of long distance connections which many places dont have ! So an exchange may not bring in Good results in my opinion!