In no particular order:
Getting to SJPP isn't as hard or as scary as I thought.
Finding an albuergue isn't hard or scary either.
Getting the credencial and having it stamped is not difficult AT ALL. Get a decent dry bag that is easy to get into to keep it in. Keep your actual passport handy too. A lot of albuergues wanted to see mine (WHY??).
Carrying a lunch and a snack the first two days is a really, really good idea.
I am miserable without enough water.
The rain in Spain is mostly in the Pyrenees and Galicia.
I don't like grilled Pulpo.
I didn't need to pack deodorant, a pillow, 3 changes of clothes, a head lamp, a silk liner, a Bierley guide, potassium, can opener, or bar soap.
A couple of extra zip lock baggies will come in really handy.
The things I used every day were the most important things:
clean socks and underwear, walking poles, warm jacket, rain coat and gloves, buff, tissues, smart phone with camera, flashlight, kindle app and music with ear buds and blister treatment and prevention stuff.
Take a cab into Pamplona, Leon and Burgos. I hate walking on cement - particularly in traffic.
When the weather is nice and I am sick of long sleeved tech shirts I can buy a T shirt just about anywhere.
If my pack is too heavy I can just send it ahead with Jacotrans.
Whatever the difficulty is, whining won't change it. Just keep walking!
Walking poles look ridiculously similar. Mark yours up with stickers or something.
You can wrap a little duct tape around them for just in case.