Telestial vs. Terrestrial

Today's reading assignment was D&C 76: 71-113. The verses here differentiate between the criteria to make it into the terrestrial vs. the telestial kingdom. Now I remember being 12 (okay maybe even 16) and never being able to remember which was the lower or the higher of the two. Thankfully Danny Fudge came up with the perfect way to remember which was which, and now I never have a problem remembering which one comes first so the solution is fool-proof :)
You see, telestial has an L in it. L stands for Loser, and the telestial is the Lowest. I just helped you, you will never again forget which kingdom is the lowest because they're all losers. I imagine a bunch of people with big L's on their forehead floating around down there.
This reading section however caused me to mostly reflect on the differentiations between the people in each kingdom. The scriptures lay out some pretty good guidelines for who goes where, but at the same time I see a lot of gray area. Like there are people who go to church occasionally and are pretty decent individuals most of the time, but somehow lose the ability to think for a moment and end up committing some pretty big sins. Are they judged for the majority of their lives, or the few weeks days or minutes where they did something wrong? It makes me glad that I don't have to be the judge of those situations.
Mostly I've been thinking about my Uncle Carl. He committed suicide and was a pretty strange fellow most of his life. However, prophets have told us that if parents are faithful to their temple covenants then their children will not be lost in the grand scheme of things. I sometimes wonder if there is a caveat for situations like Carl's where they commit an unpardonable sin. Does the faithfulness of his parents cancel out his transgression? If so how is that fair that he chooses the wrong path and still gets a get out of jail free card? If he doesn't get a free pass to the celestial kingdom, will my mom ever be happy there without her brother?
I sometimes wonder if we are too limited in our view and understanding of the scriptures that we neglect to remember that we are the children of a loving and all-knowing God. I'm sure He has these things worked out, but I'm glad He gets to sort it out and I just have to try to obey.