As far as Tatkal for Bengaluru trains is concerned, for me once all the normal Superfast trains from Satna and Bhopal (i was booking from Rewa) got filled in less that 6 minutes for 4 consecutive days, then I decided to book in Rajdhani/Duronto and since then I book in them only or as a last measure Indore Yeswantpur Weekly (I avoid it because of long route) which is normally full. ЁЯШВЁЯШВ
Even for Pune too nowadays I only use Allahabad Duronto from Satna (booking from Allahabad) as rest all are full including tatkal. Nowadays Patna Humsafar is also an option but I avoid it due to long route.