Talk to a RailFan - you will learn a LOT about Trains.

It can be seen that INDIAN RAILWAYS is contradicting its own point of ARP 120 days.
First Fare hike, In
then ARP increased to 120 days, (IR says, to make the Advanced journey planning with more comfort) so that many people who aren't sure of their plan simply book in advance and later with that much amount, IR will get good Interest. Money Minded!!!
Then...
more...

came the concept of Premium trains (or Suvidha) in December 2013.
Platform Ticket costs now ₹10. Better to buy a passenger train ticket of next station for ₹5.
Then came the idea of Premium Tatkal! Waah re IR! It have proved good idea for emergency travelers, but still it attacks on some needy people's pocket.
Then came the rule increase in cancellation charges (just to prevent the booking made by touts, as IR says), but actually this rule came just because many people who randomly have booked ticket with ARP 120 days (as he wasn't sure about his holidays and his boss didn't approve his Leave), he will pay more for cancellation! Very Good Step! Well Done IR.
Also, if you are against touts, then why did you increase ARP to 120 days?
Then came the logic of Half Child Berth system, full payment and all. I hope everybody know about this new rule.
Now I can see that in some trains, overall Berth Allocation in general quota is less than berth allocation in Tatkal quota.
In BKN-KOAA Express, Initially the berths in 3AC were 94, which are reduced to just 72, and Tatkal berths are increased from 64 to 80.
In UDZ-SDAH/KOAA Ananya, Initially the berths in 3AC were more than what they are at present. Tatkal increased from 80 to 100. Same case in return direction. Seriously, while booking the ticket in this train, when I observed this, I was very much angry.
You can also see my one old post about this nonsense step by IR. /blog/post/1153937