If you have clients, the presumption is that you know how to keep your mouth shut. You don't talk about how much money they have at Sheila's wedding. You don't blog your client list. You don't feather your own cap. Discretion: It's the better form of valor.
Discretion also means that your client has given you the right to decide for him what to buy and sell, and at what price. It's a big responsibility. Clients do sue if you're wrong - they claim their losses were caused by your abuse of discretion." Sometimes it works."