I ec'd my first, and have sporadically done the other 3. I have always used a combo of diapers and ec. I think of the diaper just kinda like underwear. It's not so much to catch accidents (though it is nice for that), but just to wear something.
I was really amazed about two things.
Firstly, that it wasn't long at all before just like I *knew* they were tired or hungry, I *knew* they had to go. There's just subtle cues that you don't even realize you are picking up on. Sometimes they are not so subtle. I have a very distinct memory of dd1 at 2 months old. I was trying to comfort her on my shoulder, and she repeatedly kept throwing her body back to put her face in front of mine. She has this super urgent look on her face. I laughed so hard when I realized she had to go!
The second is that, especially with my last one, I didn't spend a lot of time trying to ec. In fact, I'm not even sure I had done much? any? at all at this point. Anyway, one evening fairly early on, I just couldn't get her to settle down. Suddenly, past experience hit me, and I decided to take her potty. She went right away, and immediately calmed down.
There are so many nay sayers, and you'll hear all sorts of nonsense about how it's the mom that's trained, etc. It just isn't true. My babies routinely "hold it" from their earliest days. Dd1 (where I was the most in tune and consistent) could wear panties most of the time by 7m old. I would even run errands with her in them. She did have a time as a toddler where it wasn't so great, but that wasn't her fault...her daddy deployed and we traveled tons and I couldn't take her. It wasn't that she couldn't...it was that she lost trust in me. :( Right after dh got home, she started going again, and totally on her own. No potty training for her at all.