It seems this trick aint gonna work. When I selected Blr-Delhi destination and boarding Bangalore I get Bangalore waiting list (1A: WL2). However, if I try to put Pune as the boarding point it gives me Pune waitinglist (1A:WL7). So it is as good as booking Pune-Delhi.
I was hoping to get Bangalore WL, but boarding at Pune, which is surprising because you pay more.
What a bummer!