It is theoretically possible with self-study, but the problem is it's still very easy to make practical mistakes even if you "understand" all the theory. Event

It is theoretically possible with self-study, but the problem is it's still very easy to make practical mistakes even if you "understand" all the theory. Eventually you run into a problem and have to re-spin the board with no margin of extra time (assuming this is for work). In that scenario, having access to an experienced expert is immensely helpful.