Tethering: Good or Bad?

A few months ago, Texas enacted a law which forbids dog owners from chaining their dogs outside without supervision. It still allows other types of tethers tho. I've been thinking about this for a while, & now is a good time to talk about it: Is it good or bad to tether a dog?

AKC

The American Kennel club released a statement, saying that responsible dog owners should be allowed to restrain their animals using tethers, that ban on tethers would hurt, not help dogs, since some dogs are escape artists. https://www.akc.org/clubs-delegates/government-relations/government-relations-blogs/the-truth-about-tethering/

Humane Society

Most humane societies say tethering dogs is bad for them; it increases aggression & results in dogs being left outside without food, water, or shelter. That last point bugs me; it seems like it could be subject to some sort of selection bias. While many abused animals may be kept on tethers, that does not mean all, or even most, tethered animals are abused.

That does still leave the first point: does tethering a dog make it aggressive? It's easy to assume so, but are such assumptions right?

Science

Science it about testing assumptions. Have there been any studies on tethered dogs?

Yes; I've found two, with contradictory results. Both were about sled dogs, since many sled-dog owners believe tethering keeps their dogs more active than kenneling.

The first was in found no difference in the dogs welfare, if they were trained to stay on a tether. The second was in found increased aggression, if the dogs were not exercised.

If you ask me, both studies make sense. 

Here's a link to the first; I'll link to the 2nd when I find it again: https://www.researchgate.net/publication/237479574_A_Comparison_of_Tethering_and_Pen_Confinement_of_Dogs

And here's the 2nd: (PDF) Comparison of tethering and group-pen housing for sled dogs (researchgate.net)

Bible Verse for Today: https://www.biblegateway.com/passage/?search=2+Chronicles+7%3A13-14&version=HCSB