Two bank accounts: Isn't it convenient?
To me using two accounts is indeed convenient. Think of a situation when you have a loan from one bank and you also have your business account there. Imagine you do not have money on your account and the bank is waiting for a transfer to cut the money, but you do not want the money to be cut. You can always ask your customer to transfer fund to another account and so you can avoid money-cutting.
In fact I use 3 accounts for my company: 2 normal (onshore) accounts and 1 offshore banking account from Jersey. It is quite convenient. My country's banking system is quite volatile and exchange rate often experiences large fluctuations. I keep significant amount of cash overseas and it is very easy to transfer them back if needed.