I have a better perspective on just how *limited* many SSPX priests are. I got to know a huge group of Seminarians from 2000 - 2003, many of whom are priests today.
One, for example (I refuse to give or confirm his name, as this is not about personalities) went right into the seminary after Homeschooling. Talk about naive and inexperienced in worldly matters! He might be pious, he might get good grades at the seminary, but he could be quite idealistic and naive about life out in the big bad world.
And some might shoot me for saying this: but getting 100% of one's information from the SSPX and Trad Cat sources is NOT the same thing as learning it for yourself, from different sources, on your own, through life experience, out in the world.
When you rely on parents or other busy authority figures for most of your knowledge of the world, you can usually forget about things like nuance and distinction. You will be getting the 10-second soundbite, simplified version. Personally I go out of my way NOT to do this -- I'm a stickler for truth, accuracy, which makes me long-winded. But I don't want to be ham-fisted when teaching my children. But I also realize I'm the exception. I am a good teacher (not everyone is) and I seem to have a gift from God for objectivity (For humility sake I'd love to assume everyone has this gift, but life experience has sadly taught me how rare it is).
Fellow laymen over 25: You know how countless experiences have broadened your horizons, and made the world seem different somehow? It boggles my mind how many experiences I've had, which gave me a broader (and therefore, higher elevation) perspective and more accurate perception of the "whole world".
How could a young man of 18, who never left his hometown (let's say a majority white town in a conservative/rural area), POSSIBLY have an objectively accurate (i.e., realistic) perception of the world? He's been almost completely sheltered his whole life. How many experiences, how many kinds of people, are but cardboard cutouts or "placeholders" for the real thing?
I remember being shocked to meet someone so naive and sheltered, who was only 4 years younger than me at the time. He wasn't 18 any more, because he had been in Seminary for a couple years already when I got there. I don't remember what the issue was, but my 6 years "in the world" made me seem closer to being his father than a peer of his!
You don't want to throw kids to the wolves at 5 years old (as the world advocates) and you certainly don't want to throw your kids into a grave occasion of sin (like public school, or hanging around children who WILL introduce them to grave sins and vicious behavior). I think the solution is to form them well, in the Truth, but at some point you have to let them live and experience the world themselves. It's called growing up.
But let's just say I wouldn't want any 18 year old writing moral theology manuals...