If person A is 1 contract call long, and person B is 1 contract call short, and they both close their position with each other, then volume will be 1. If big player offloads his 1000 contracts call long, then two things can happen: (a) If fresh buying orders are triggered, then volume and OI will not change much. (b) If large stop-loss orders are hit then volume change will be large and OI will also decrease.
Please correct if I have wrongly analysed above two scenarios for the query. When Nitin sir gave alert at 10:48 am that a big player has offloaded, I saw on 1 minute chart there was a HUGE SPIKE IN VOLUME BAR along with decrease in premium. Then I got confused that why we talk about less volume when discussing about big players…?