Okay, well I seem to find the answers to your questions in those postings, but I could be wrong. I'll write what my understanding is and maybe that can help you come to your own understanding. I have assumed that the data in those links was true. I have assumed that you want to prolong the life of the batteries in your car. So:
1. Inapplicable. No distance matters when deciding to charge. Just the bars on your car matter. It was written that you should charge to keep your battery charged between 2 and 10 bars.
1a. Inapplicable. 30 miles remaining is meaningless. Use the bars. Keep the battery charged between 2 and 10 bars.
2. This was not really covered in those documents, yet it would be not recommended based upon a little thinking. Charging stops when it is full. Leaving the cord plugged in will not do anything more than allow a full charge. But now you're doing a full charge and ignoring the advice to keep the battery between 2 and 10 bars of charge. This is, I suppose, unless you are using a timer, in which the thing is still plugged in, but no longer charging.
2a. It's no different than doing a full charge, which is not recommended.
3. Yes it is a problem in that a full charge is not recommended. Voltage, ambient temperature, and the color of your car are not listed as they are not pertinent information. DC fast charging is not recommended when trying to prolong the life of your battery. That is pertinent and sort of related to voltage I guess.
3a. Yes, doing full charges will shorten the life of the battery.
I'm interested in your thoughts on this. Maybe you have more information to share. Maybe you disagree with something. I'm an engineer and I'm always learning, so my answers sometimes change as I learn new things.