This would greatly reduce the amount of actual bitcoin transactions needed, thus taking pressure off the network. The bitcoin network would resemble more an "interbank clearing network" than an "all to all transaction network". Since small transactions, such as buying a cup of coffee, only result in an internal ledger entry in the bank, they can be done instantly. Furthermore, having less transactions on the network makes it run faster overall (solves "confirmation delay" problem).
I will have to strongly agree with this.
People are focusing too much on the need for BitCoin handle the 'last mile' of the financial transaction.
I however think that its actually strength in not in this area. Right now it is a store of wealth (due to its deflationary structure) and a means to transfer a huge amount of currency across borders.
To add any other capabilities really may require an alternative currency.