The more transparent just mean you no longer need to window shopping and inquire how much negative spread each bank is given. It all shown in the BR rate. Before BR you only know BLR is 6.6% but the minus spread is upon negotiation with the respective bank, so you won't know the minimum "base" rate you are going to get, since BLR only change in longer interval compared to bank changing their minus spread. Hence when you negotiate with banks, you won't know how much negative spread is determined by market force, and how much is due to your own credit risk. It will be able to "see" after base rate introduce and what you negotiate with banks is purely your own credit risk, and thus greater transparency. The banks can't tell you: oh, the negative spread offered is different because its how the market is, not your credit issue.