Like th op, I'm 42 and started learning with Rocksmith. Trying to figure out the different learning tools like YouTube, dedicated online traing sites etc. has become part of the learning for me. Rocksmith has inspired me to take lessons (started a couple months ago) after 2 years of playin the video game. Maybe I'm stubborn, silly or both, but rocksmith taught me enough to gain confidence to go get lessons. Sounds silly to younger guys maybe, but I felt kinda foolish starting lessons at such a late stage. I felt RS gave me a head start on the lessons and made me a little more than a complete beginner.
Having said that, I will agree that in-person lessons is the way to go. It has been the best way to learn so far. Before or after RS...I probably wouldn't have taken lessons at all was it not for the game.