The interaction of mutation warrior with the extra discovery feat

See title. Can the mutation warrior fighter archetype, once he hits level 7, take the extra discovery feat to specifically take one of the discoveries the archetype allows him to take?

The archetype states "The mutagen warrior uses his fighter level as his effective alchemist level for the purpose of these discoveries." so there is some ground for this possibility, and a gm would certainly not be wrong to rule it either way, but I wanted to seek an official ruling on the matter.

I've seen forum discussion of this topic before, but no explicit arbitration from anyone at paizo, hence I decided to ask.

I'd say absolutely. So long as it's on the very limited list and you qualify for the level. Your effective alchemist level is pretty much the words needed to count as an alchemist with discoveries

Personally I wouldn't have a problem with it.

Strictly speaking though, I don't know that the 'Mutatgen Discovery' class feature that the Mutation Warrior gets counts as the 'Discovery' class feature that the extra discovery requires.

I know their have been some FAQs on class features with changed names and/or slight changes (we have both in this case) and whether they count as the 'parent' class feature or not. I don't have a link to them offhand (perhaps someone else will supply that.) Personally, I found them to be pretty inconsistent and confusing.

The mutagen warrior uses his fighter level as his effective alchemist level for the purpose of these discoveries

I'd say he counts as having the Discovery class feature, based on other FAQ. But I don't think he would get to use his class level for qualifying for extra discoveries, as they wouldn't be part of the "these" that give him an effective alchemist level. I wouldn't see a problem with running it the other way anyway though, if someone wants to houserule a little.

Consider a mutation warrior 7/alchemist 4. He takes extra Discovery. What level does he count as for the discovery?

But I don't think he would get to use his class level for qualifying for extra discoveries, as they wouldn't be part of the "these" that give him an effective alchemist level.

I can't see that being correct. Assuming that Mutagen Discovery works, the extra discovery is adding a discovery under the umbrella of mutagen discovery. The two remain connected.

Consider a mutation warrior 7/alchemist 4. He takes extra Discovery. What level does he count as for the discovery?

I am pretty sure you would have to specify. Just as if a Witch/Shaman took extra Hex they would have to choose a witch hex (using the witch class feature) or a shaman hex (using the shaman class feature).

I don't know. This text is way too similar to the warpriest text in my opinion.

At 3rd level and every 3 levels thereafter, a warpriest gains a bonus feat in addition to those gained from normal advancement. These bonus feats must be selected from those listed as combat feats. The warpriest must meet the prerequisites for these feats, but he treats his warpriest level as his base attack bonus (in addition to base attack bonuses gained from other classes and Hit Dice) for the purpose of qualifying for these feats.

And if there was a feat that gave 'Extra Warpriest Bonus Feat' I would argue that the feat granted by that feat would follow the rules for the other Warpriest Bonus feats as well.