Does shield give protection when used with automatic (2H) weapons?

I have crafted a metal shield. In the talent tree, I went down all the way defense path.

I am planning on getting a Shield Master perk on next level-up

All skill points go into towards automatic weapons currently. When fighting with AK-47 I have noticed that character puts a shield on his back.

If this means that shield does not 'count' when using 2H weapons, it would make sense to spend next perk on something different then Shield Master and throw shield out just to save some weight (9kg) and use bag instead.

Does shield give protection when used with 2H weapons?

According to this thread

The shields have a %chance to block damage from front or back depending on where it is. The metal shield has 50% chance and BZT has 99% afaik. Shield on the back has lower %chance for sure, but I don't know exactly by how much. Also with most armors having a %chance to block all incoming damage testing shields to get a better idea is a pain so I just never did it. Having a general grasp on mechanics is mostly sufficient for this game.

So, for survival BZT is an obvious pick as well as the fact that facing matters. You can adjust your facing by clicking on the square you stand on, which is useful sometimes.

Also one guy did some testing

Fidel burst shooting at my character with PPS43, at fixed range, a fixed level,
- MC with only fair dodge without shield, Iron Cast Shield, character level 13, an Armor probably the 6B2, no shield ability.
- For results bother only on 0 damages hits and hit missed
- Didn't tested side shooting.

1H+Shield+Direct facing: 12 zero dmg hits, 0 hit miss.
1H+Shield+Direct back: 0 zero dmg hits, 0 hit miss.

No shield+Dodge 8+Direct facing: 0 zero dmg hits, 3 hit miss.
No shield+Dodge 8+Direct back: 0 zero dmg hits, 0 hit miss.

2H+Shield+Direct facing: 3 zero dmg hits, 0 hit miss.
2H+Shield+Direct back: 6 zero dmg hits, 0 hit miss.

The conclusion is facing matters, even with a shield on the back and without shield, even more with 1H+Shield.

The facing UI is very unnatural, but I gradually get used to it, I think the best is use Ctrl to choose facing direction with mouse at end of turn and after any order to companions, then release the key.