Re: PT vs. PL?
I used to think they were the same thing, but my views have changed.
If you set out to "Train" your child to use the potty (I don't find it offensive at all, BTW :-) ) your are learning to recognize their signals and when they need to go- or just getting on a schedule of taking them however often. For us, with DS, this completely backfired, and we, too ended up going back to diapers, and I was completely frustrated.
To me, potty learning is waiting for the child to understand and learn to respond to their own body cues in their own time- when they are both mentally and physically ready.
The more and harder we pushed him to "train" the harder he pushed back, the more stubborn he became- even with treats, rewards, etc. and even though he sometimes knew when he needed to go, he wouldn't. The more I backed off, and let him take the lead, the more he started to lead, and he is choosing more and more to go to the potty. I change his diaper without comment (usually- I'm only human!) and sometimes he will ask to put on big boy underwear- or he'll take his diaper off on his own and go potty and then put on underwear himself.