Sir, Kindly check ur logics!!
1. SLR/GN are @ Front & Rear, to provide troublesome movement through Vestibule, across Reserved Coaches!!
2. AC Coaches @ extreme end of SL Coach Series, to facilitate unhindered movement for SL Class, anytime, even whn AC Coach Vestibule are closed @ night. For the same purpose, Pantry Car too mostly is attached with AC Coaches (as they too shut the vestibule opening down)
3....
more... Many PF are small & normally SLR/GEN along with 1 or 2 adjacent AC Coaches cross PF.
4. If Parcel/Luggage/Crowd are the issue, then AC Coaches would be attached in middle normally, which isnt been done!!
5. Further, while u alight @ station (casually for tea), adjacent coach been GEN, makes u feel stinky (overcrowd, noice & overused washroom). So again its not about Passenger conveinance, but IR Conveinance!!
etc etc...