Please note that e-tickets ALWAYS require ID proof of one of the persons on the e-tickets, whether it be tatkal or normal booking.
The rule regarding Tatkal no longer requires ID proof is for normal tickets, NOT etickets. This was a requirement earlier for Tatkal tickets, issued normally also.
The problem is that there is lack of coordination between two organisations, the CRIS and IRCTC.
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this is NOT an official site.
The reason why e-ticket requires ID proof is very obvious. In the case of normal tickets, there is proper documentation in the form of a form filled in with details of address (even if it be false !) and a signature and a counter number issuing that ticket. This is not the case with E-tickets. Hence the need for ID proof. The i-ticket as it known, has some imprints on it which make its easy to detect as printed from the PRS.
In case of special checking squads coming in, they normally carry the stack of reservation forms to verify the passenger details, and even normal ticket holders are asked to show some proof that they are the passengers .. it can be any ID for them, an office letter, a visiting card, a photo debit/credit card, or even a ration card, anything which proves the name. They are queried about the address given so as to ensure its reliability. That is the standard process.
In the case of E-Tickets, ID proof is mandatory regardless of TATKAL or any other Quota.
I hope this explains the process and the reason behind this.
As I said, this rule has created some confusion about carrying ID proof. I always advise passengers to carry some ID proof while travelling, not only for this purpose but for other purposes as well, such as illness etc. It is in your own interest.
good wishes.