Yep, this. I've been playing and singing for 40 years and I still find it challenging, to a point. One of the two things needs to be automatic. Usually for me that's the playing, because singing well requires a lot more concentration than playing well does. What's frustrating for me is that when people hear me while I'm in the middle of working stuff up, they think I can't do either one of those things well. But it gets better.You have to get the bass line down so well you don't think about it, then add the singing. Or get the singing down so well you don't think about it, then add the bass playing.
