I've been playing for 5 months now, and I just turned a major corner, and I'm so pumped up I feel like I can play a real game of golf, as opposed to just bringing the club back and hoping for the best in my swing.
Like most, I couldn't figure out why I would hit fades, slices, & bananas so often.

Sure I'd hit straight shots, and even some pulls & hooks, but on average it would be mostly shots to the right.
Well go figure, it took a couple of articles from GOLF Magazine and Golf Digest to open my eyes.

This is after 5 months of going to the library and looking at every golf instruction manual published in the last 50 years. I know many think that these magazines and books are not useful, and will contradict themselves often just to keep us confused,

but this time it worked.
The tips that worked are "The Power Move" in Golf Magazine, and the "Breaking 100-90-80" in Golf Digest this month (where they use the driving analogies).
What they basically showed me was, during the downswing (which should be 80% effort) is to
"twist and lean". That is, to 'twist' my arms to rotate the clubface, and to 'lean' into the shot so that I shift my weight to the left at impact.
Oddly, it was one small picture of a Tiger extension after impact that did it for me out of the whole article.
I saw that his right arm was pointing at the target and his right palm was perpendicular to the ground when he brought his right arm parallel to the ground after impact. I was always pointing out towards the right and/or had my palm facing up by 45*. By forcing myself to get my right hand & arm to that position at that point has cured my slice. (note: this is also the same thing that Pennick teaches when he demonstrated positioning your hands like you're shaking hands with someone on either side of you during the swing, but I just couldn't see it when I read it then).
Then there was the 'lean' part of it.
I saw that to get extra distance, you need to de-loft the club at impact and turn a 9iron to a 7iron by shifting your hands forward about 2" at impact from where they were at setup. The only way to do this was to complete the weight shift to the left and feel like you are leaning forward at impact. I immediately got 10 yards on my shots. You also force yourself to hit down on the ball (getting extra spin) instead of sweeping it.
Once I got this, I brought it to the range (haven't had a chance to play yet) and in the last 3 trips, I've hit about 10, then 5, then 1 shots that were definite slices (out of 75 balls to a bucket).

Each time I worked on these new items, and it has paid off. As opposed to my usual range sessions, where I would hit balls that land on one side of the range to the other.
I now know that if I don't concentrate and do this on every shot, then I am wasting my time. I also understand what it means when golfers talk about taking one side of the course out of play. I did some simple geometry, and given a fairway that is 30 yards wide. If you are inconsistant and hit the ball on any one of the 9 ball-flights (from duck hook to banana slice) with no direction any more likely than the others, then you have only a 35% chance of landing in the fairway. But if you can take the slice/banana away, you'll have a 56% chance of fairway. And if you aim for a tendency to fade/hook, you can probably bring that up to 2/3 chance.
So to sum up, you are wasting your time if you don't
a) twist your arms so that your right hand is pointing towards the target and right palm is perpendicular to the ground after impact
b) feel like you're leaning forward a little too much at impact so that you can de-loft the club and hit more down on the ball and get extra distance