Hi J.,
I don't have much helpful advice about adjusting naptime for daylight savings, since our 17-month-old daughter has a very wide variation in her naptimes (depends on the day). But maybe adjusting naptime 10-15 min per day might work? I was thinking of doing that with bedtime for my daughter, but she actually ended up adjusting in one day on her own. As far as Healthy Sleep Habits, I must admit I haven't actually read that book, but we did do a "cry-it-out" of sorts with our daughter, and it ended up working really well for us, she sleeps great now. We started it around 11 or 12 months, I think. For the first couple of nights she cried for 30 min to an hour, but after a few days she fell asleep without crying. It was SOOOOO hard to hear her cry, but I just had to let her learn to fall asleep on her own. And it definitely worked. Now she only cries at bedtime on rare occasion, like when she is teething. If she wakes up during the night (which is rare), I let her cry for a couple minutes, then she falls right back asleep. I have made the mistake of going into her room before when this happens, and when I do that she is literally up for hours, wanting to play, etc. She ended up an overtired, cranky baby the next day. For us, it just does not work to go into her room if she cries (unless there is something wrong, of course - I always have the monitor on, and I peek through the door to make sure she is okay). Otherwise she is a very happy, well-adjusted girl. I know there is a lot of controversy over this method, and I truly believe it depends on the child whether it is appropriate/effective or not. For us, it definitely worked, and everyone in the house is getting more sleep and is well-rested, especially my daughter. So whatever you decide to try, I hope you end up finding a solution that is right for you and your son!
M.