Correct.

It is the different ABILITY scores of the seaman that boosts the different abililties of the other sailors.

Seaman used to be thought as generalists and that they boosted all other sailors by the same percent. Testing has
shown that they can be/are specialists boosting more in one abillity then another.

For a SS, you would want a seaman with Hi potential to boost air and sonar and you would also want
high repair and restore numbers to help with HH and DC damage. High torpedo ability along with great
engineering ability wouldn't hurt either. (SS crews are real specialists-to get a seaman with great abilities in
everything is ultra rare. )

For a CV, you would want a seaman with High Fighter, Bomber, and perhaps Aircraft ability. Of course High repair
restore numbers wouldn't hurt either. High potential would help boost the medic ability and start to reduce casualties.

In testing, one player found that an IJN seaman with high torpedo abilities signficantly reduced torpedo reload time.

For a gunship, particularly AA, High reload ability is foremost. Your choice from there. You could consider high repair/restore to minimize damage. Hi AAW to knock down nearby enemy TB or DB. Hi Engineer abilityto help boost speed.

Sorry both incorrect for now.

Using restore to prove that a Seaman uses the normal stat abilities instead of the potential stat to boost an ability is pointless.
I have a seaman who provides 98 SD on his own. You would think if I put him in a crew that not only would he provide that 98 SD on his own, but also boosts the SD provided by the other sailors.
Guess again, Restore seems to be a special case.
I can put together a crew which has 798 SD, that crew plus the 98 SD seaman should have more than 896 SD, cause he has his own ability and is boosting those of the rest. But he isn't, SD remains 896.
That same seaman does boost reload by about 3% at my last check some levels ago ( gained levels and vets, lost all experts since then), so I should see at least 900SD.
Concluding that a seaman boosts abilites via each corresponding ability based on the SD difference between a base stat 10 or 11 restore just isn't correct, any difference is purely down to the base stats giving greater inherent SD rather than greater boosting of the rest.

The only way to really see what stat is used to boost ability is to have 2 same level seaman, with near enough the same experts and vets and vastly different reload and pot base stats.
Until someone does that we don't know for sure what stat a seaman uses to boost others.

No.

You didn't show anything.
Noone yet has conclusive shown what stat a seaman uses to boost other sailor.
I'll repeat, using your example, 1 with 10 the other 11 base restore, proved only that the 11 base seaman provided more inate SD than the 10 base. Seaman do NOT boost the SD provided by other sailors

If you want to determine if a seaman uses Pot to boost all stats or uses acc to boost acc, rel for rel etc,you use 2 seaman, same level near same vets and experts, but with very different Pot and the stat you want to check and check whether the higher pot or the higher other stat gives the bigger boost.
You can use reload to prove it one way or the other, torpedo will also work. Working with 1 engineer that is at the threshhold of gaining more speed for OH on some ship, might also prove it fairly accurately.
As I've shown you can't use restore, using OH time and repair speeds is very inaccurate given the problems in accurate timing and in the small difference a seaman makes anyway, if you can even measure the difference.
Air/fighter/bomber are even harder to determine the difference between the use of 2 different seaman, as there are a lot more of other factors involved.

In testing, which I and others performed, found seaman boosted SD.

One example. One sailor on board have an SD of 50. He was removed and a 1st seaman replaced him.
This gave an SD of 50.

Then the seaman and the first sailor on board were placed on the ship. Instead of a total SD of 100, the SD became
104. Where did the other 4 come from? My Seaman ABSOLUTELY boosted SD.

These were removed and other sailors were placed on board and tested one at a time recording their SD.
Sailors were removed and replaced in groups. Always the SD summed with no magic increase. Placing a seaman ALWAYS boosted the SD greater then the sum total of the individual sailors. As more sailors were added to the ship,
boost amount became greater. The boost increase was also a function of the number of sailors on the ship.,

Tests found that seaman whose abilities in repair/restore were lower did NOT boost SD as much, or in some cases, not at all but were a strict add. Obviously the programming of seaman boost is not a straightforward addition. to ability or SDE.
Thus your claim that seaman do not Boost inherent SD is both correct and incorrect. My seaman certainly boost SDE. . Yours may not. Correct for you, incorrect for me.

One of the rules of scientific testing is repeatability with controlled conditions. Unfortunately, there are a ton of variables that cannot be controlled, different players, different seaman with different abilities, different lvls, different numbers of vets and experts and so on. This leads to different results and different conclusions.

And as for the stat used, if you dig through some of the NF documentation (A boring read) you will find that NF says that seamans abilities are a percentage, not an actual ability. The implication is that these Percentage numbers are related to the boost ability

Interesting on the boost of OH speed by 1 knot.

Others have seen the OH speed effect when testing seaman. It shows up during the game, but not in Harbor. In testing, my seaman do not boost OH speed. They boost SD but not engineering/ OH speed-time. In fact, one of the other testers I communicated with found his seaman boosted OH speed, but did not boost SD excactly opposite of my seaman.

Then again, my seaman have high repair/restore percentages and lower engineering percent which is a possible explanation.

How and What a seaman boosts is not a simple and straightforward answer. Although some NF documentation says it boosts onboard sailors ability, it is not an across the board, simple additive boost. Instead, some abilities appear to be boosted and others are either untouched or if an ability is being boosted, the boost amount has no impact.

Happy testing.

Here we go with SD data.
Ship is DDX set up for ASW.

SD of each sailor

Bridge Op 0
Sonarman 34
Gunner 20 (this is a premium gunner used for HH)
gunner 10
gunner 12
1st seaman 40

Total SD if added separate 116

All on board SD 122 or 6 more then summed singularly.
Increase by about 5%

Again with same crew different seaman
Bridge op 0
sonarman 34
gunner 20
gunner 10
gunner 12
seaman 24

Total SD if added seperate 100
All on board SD is 106 or 6 more then added

Increase of 6%. Note that the "different" seaman has almost 40% less
built in SD but boost is 1% higher.

I am not sure if a seaman would do much when you are at higher lv. But if you are a believer amd want to train a FW seaman, I would say got for the elite fp to class as a seaman.
I personally have 2 seamans in US, one everything 10,po14. one elite fp seaman. The deal is, I test them in 3 cases, to test them for oil efficiency and AAW res.
The results are the same, no matter which one I put on board or even without any. The plane last about same time, and res time also make no identical differences.