I happen to travel on the 12223 LTT-ERS Duronto AC Super fast express in A2 Coach (last week of December 2013) and found it to be a really super fast train. But, unfortunately, the railways don't want this train to be 'the super fast train'. My observation is that this train has few technical halts (which is necessary for crew change, filling water, refueling etc)) Apart from that, the train also halts at some small stations to give way for other trains. Now if these halts could be reduced and this train given importance to pass by over other trains on that route, this train can achieve its full run in less than 20 hrs (ERS destination). I experienced it myself. The train arrived at Shoranur at 2.55 p.m. and stopped for only a few seconds. Thus it could reach ERS in 1.5 hrs from Shoranur (it reached TCR by 3.25...
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pm. halted there for almost 7 minutes), then en route it stopped at Angamali, Alwaye and later entered ERS junction by about 6 p.m. (as told by a co-passenger who travelled up to ERS, I got down at TCR as my actual destination was TCR).
The service on the train is very good. The food is extremely good and the train kept clean all the time. However there are sudden jerks on the coach (A1 and A2) which can jolt you from your sleep. This more or less happens when the train is slowing down or starts after a stoppage. Please maintain the quality of service all the time. If the train arrives before time and made to stop at some important stations (before ERS) is welcome as people who want to get down at these places can do so. Even if it stops for a minute or two at these stations (Trichur, Angamali, Alwaye) the train can reach ERS by 4.30 or 5 pm. Co-passengers told me that the train halted at Panvel and even passengers boarded from Panvel, which to me was quite strange (as it's a point to point train- boarding from LTT (12223) or ERS (12224) only) .
On the return leg (first week of January 2014) I was in A1 and found the quality of linen extremely bad. They gave used bed sheets and no towels as napkin. The food quality was really good. Similarly this train is made to stop at many way-side stations to give way for other trains. If this is disallowed the train can reach LTT by 4.30 p.m or even at a lesser time. My train did not halt at Panvel and it disappointed quite a few. A halt of minute or two will be helpful at Panvel, if the train is before time. (If I am not mistaken, this train used to reach LTT by 11.45 am when it initially began its journey, right?)