Yup, even if you're a rockstar lawyer, it's always good to have one because your lawyer views the case in a more impartial manner with out the emotional attachments that you may have to the case.

It's pretty easy to get blinders on if you're representing yourself.

It's not just that; AIUI if you represent yourself, you can get in a lot more trouble for saying something later decided to be false, or making a statement not supported by evidence. There are explicit bonuses built into the system for those who have a representative.