"Just under 5 hours of pushing"

Wow!! I'm impressed that a doctor actually let you push that long without shuttling you off for a C/section!! That in itself is a miracle- let alone waiting so long to do an episiotomy!
Position when pushing seems to have more to do with it than the baby's head size. Lying positions are just not good for ladies with a history of tearing, and I can attest to that- both tears I had were while lying. (Well... the first one was a continuation of an episiotomy while in lithotomy with stirrups, the second was just a tiny tear but I was flat on my back again...

) It forces the baby to have to curve upward to get out, which puts added strain on the perineum making a tear more likely. When you are in a squat type position, whether a full squat, supported squat, or sitting squat, the exit route is wider and shorter, with less curve for the baby to need to maneuver- even standing to deliver can open you up more... These are all beneficial to avoiding perineal tears...
(You are also more likely to end up with forceps when in a back-lying position- it is just not a good way for baby to try to maneuver out of that pelvic obstacle course..., for some ladies position is the best tool that they have for helping their little ones come out...)
I know of a lady who birthed a 13+ lb baby without any tears...

There are other factors that play into it in some instances, but for the most part oiling to reduce friction, and finding a good pushing position that really moves the baby down will overcome most problems. Don't be shy about changing positions if something isn't working, and sometimes a good hula/belly dance can shift those hips around and help a baby who isn't wanting to descend... (just getting up and walking a couple steps can have amazing results in getting a slow baby to really clear that pelvis...)
Knowing how to direct your pushing can be a big help too, a trick I read about is to place your hand on your pubic bone and push toward that, often we are told to push like having a bowel movement, but that really doesn't direct the energy quite where it is needed. We want those muscles to push out, not down...

I hope that helps some!

Tears do happen sometimes, but fortunately birth is so intense that you don't really feel anything until afterward- usually during repair... and if you use dermaplast and keep the stitches rinsed, it should heal without too much trouble. Usually a natural tear will be a first or second degree tear, which heal easily and leave little scarring. Do lots of Kegels to help restore circulation and muscle tone to any areas that have torn recently, or in the past. And if you have a little tear, ask about medical superglue, some midwives carry it if you ask... it makes for effective, speedy repair and healing in little tears that might otherwise result in an annoying skintag (like the one that I ended up with after the tiny tear, my husband ended up having to help me cut it off...

)
The Lord bless you all!
Zoie
http://groups.yahoo.com/group/Godsbabycatchers