#1
Guitar strings should't be too far from their breaking tension. A hi e as a low e will sounds very floppy and won't hold in tune very well. The farther a string is from breaking tension the harder to tune. The closer the string is to breaking tension the quicker it will settle in tune. Strings should be close to breaking tension to an extent to sound good.
#5
Strings don't have to be close to breaking tension, they just have to have enough tension to not flop around like a high E tuned to a low E. "Proper tension" doesn't mean a string should be anywhere near its breaking point. Most strings can take an awful lot of tension, and it's really irresponsible to tell people to put that much tension on without really specifying what that means. It's certainly not a useful statement.

I don't think we need threads telling people not to use wildly thin gauge strings, and we certainly don't need threads making absurd claims about how strings should be used close to breaking tension. This seems like poorly informed pseudo-information.