Oh, my. I’m glad I knit this, and I am so very satisfied with how it turned out. However, there were points that I wasn’t sure I could get through. The pattern assumes a ton and can be very vague. There are also some math errors (in some of the sizes) that make it a bit aggravating at times.
I knit this in a 6 year old size for my rather large 4 year old. I wanted him to have a little room to grow into it. He chose the yarn. I was hesitant about it at first, but now I think he made a great choice. He also helped pick the buttons (I did a lot of steering on that one, though). They are plain wood buttons, and I think they really add a nice touch.
I used all but a few yards of the 3 skeins. I bought an extra, so I’ve promised him a matching hat.

As far as helpful hints go:
BasqueKnits’ notes and photos helped me. http://www.ravelry.com/projects/BasqueKnits/gramps-cardigan

Also:
The sleeves seemed too narrow, so I cast on 40 stitches instead of 32. When increasing the sleeves I went up to 54 stitches instead of 50.
There has now been an update for the written sleeve cable pattern, but it was a tad off in the original. So if you’re working from the original pattern, get the update. It’s free.
There’s a small (but frustrating) math error in the Buttonband and Collar row. To make it work I had to pick up and knit 83 stitches on the right and left fronts. I noticed some of the sizes were fine on this row, but some had errors.
I’m no short row expert. I was definitely confused, though. I’m not sure if it was just my own shortcomings or an error in the pattern. I kind of figured it out, but I ended up making the buttonband and collar too big, so I think I must have added too many rows.

Overall, I am super pleased, and this was a very satisfying knit. I’d love to give it another go sometime. Maybe in a smaller size for our new baby.