Sola appears to be cloaking her identity (intentionally?) throughout Ship of Theseus. This presents an interesting counterpoint to S’s situation: S is searching for his lost identity, while Sola appears to be concealing her known identity.
Here are clues that seem to indicate this. Please discuss your own observations in the comments…
- She goes by different names (Sola, Szalome, Samar)
- She costumes herself as a man in El H__
- She changes roles repeatedly
- Wealthy traveler on the liner Imperia, appearing as a casual reader in the tavern
- Factory worker in B__
- Part of the resistance in El H__
- Companion to The Lady on Obsidian Island
- Traveler on a ship like S’s
- She is the girl in the century-old picture in El H__. And Khatef Zelh, when describing Samar, describes at least six separate roles she was known to have possibly played. Is it because she played all of them and different people are describing the Samar that they knew at the time?
- She somehow seems to keep up with S’s valise in an undercover manner.
- Someone seems to have obtained Stenfalk’s valise between B__ and G__. S left it at the base of the limestone wall but notices that the agents don’t have it when they arrest and murder Stenfalk. Sola was last seen in B__. Did she follow the group and recover the valise?
- After S receives what appears to be the same valise in El H__, he is stripped of it briefly by a would-be assassin. Sola returns it to him, costumed as a man.
- Sola recovers the valise that S left in The Territory after his encounter with the Governor and returns it to him in The Winter City.
- Sola ensures that all of S’s supplies in the valise are in order before he takes it to Vevoda’s chateau.
- She somehow seems to be aware of and secretly spying on and/or working against Vevoda before S even knows who Vevoda is.
- She is in the tavern in the Old Quarter, appearing to casually read a book but probably watching one of Vevoda’s agents/detectives who is there taking notes. (16)
- She secures a job in Vevoda’s factory under the name Szalome, doing some sort of book work that Pfeifer didn’t think needed done before. (116)
- She leads S to the two detectives next to the Central Power plant so that he can witness the bomb exchange. (100)
- She (probably?) is the one who rescues Stenfalk’s valise from the posse of detectives. (172)
- She obtains the map to Vevoda’s chateau, along with the intelligence about the gala nine months away and find’s S in the Winter City in order to help him confront Vevoda and write the ending. (401-402)
- She and S both conceal their identities together while on Vevoda’s estate as they prepare to confront him and his guests.
Is Sola concealing her identity? If so, why? And why conceal it from even S, as in El H__ when she is costumed as a man when returning the valise? What are your thoughts?
Thoughts On "S" 
I think you are right. From Straka’s position, she is elusive more in the way of a muse and not so much as a romance interest, from her viewpoint, she seems to be more of the almost omniscient über-agent who is delivering him enough info to evade and play the worlds most dangerous intel agencies. On this path of spycraft, i don’t think S. is clueless and without memories. As far as the cloak and dagger buisiness (like infiltrating S.) goes, he might as well only pretent to be unable of remembrance, purposefully suppressing his identity, or having been conditioned for ignorance.
On antoher level, that of the inexperienced writer or private person, he might on the other hand be lost and without memories or identity.
As for her involvement of the war against the Vevodas of the World, and her uncanny knowledge, she might well be one of (or The) higher ups or event leading eminence of S. because of her knowledge. On the other hand she is the emotional, driven one, so her hiding and masquerading may be due to her involvement and ambition, where those subterfuges are not used to hint and refer to other leads to teach some history to make more connections (as perhaps seen with Samar).
I have considered Sola/FXC to be the true Straka in one interpretation, but i think the clues are too ambiguous to conclude it only a bit more persuasive than say the Summersby or MacInness lead. In any way, her connection to The Lady is the main give away in this reasoning. The Lady knows everything, she is in possession of all the plans and blueprints of the Stories, so she might as well be the real Straka, and Sola’s apprenticeship to her and her free access to all her secrets suggesting that Sola as the emotional personification of the writer having the most insight and the most active part, since she sets everything in motion by enchanting S. to follow her, her preparing the way, leading him and rescuing him from time to time.
In that way, S. would be the convenient red-herring that draws attention away from the real actor, Sola. That thought would be a lot more convincing if Sola was presented with more of her own character instead of a shadow.
The fact that it is always her recovering the valise is very interesting. The valise contains all the tools needed for S.’s craft, so it is really his agency to effect change and do the things that define his identity. Though he may wield them, another one with the same determination might just as well, if he had made the same choices as S. did. In that case, it is again Sola who is the driving force behind the S., and poor S. the convenient tool she points in the proper direction.
to add a bit of more wild and probably unrelated speculation, if the Lady were the real Straka Author, i am reminded of the discussion about the Sobreiro. It was always in Stenfalks/Ekstroms family as we know from the campfire stories, which was already presented as odd. Ekstrom was more than once presented as a father figure, later in 1930/31 when S. comes living with him, he again writes it felt as if a lost son had come home. In Ekstroms bio, his wife left him after the expedition fiasco, and took her son with her. Sola has the family (or just one random) Sobreiro when S. meets her in the tavern, maybe she is a relative/sister, explaining his romantic/non romantic obsession. So The Lady being the Mother, Sola the sister, Ekstrom the unknown father, and in accordance with the Thesues myth, Vevoda/Bouchard being the unwordly father figure akin to Poseidon/Hermes with whom the biological father was betrayed?
“Sola” means “alone” in Italian and Spanish. In Portuguese, it means “sole,” or “only.”
I haven’t given up on my theory that the mnemonic Major system, where numbers are represented with consonants, is used in Ch. 3 and “Interlude.” In this system, 0=S and 5=L. 05=Sola.
0 and 5 are the only digits that are not represented in Interlude–“Sola” is missing.
Also: 9+41=50. Agents 9&41 were romantically involved.
Also, the name could be a reference to So La in the musical scale.
it seems like you are familiar with musical modes.. how would you transpose a regular sentence into phrygian mode?
Also, Mystimus: In Latvian, “sola” means “settle.” Didn’t you do a piece recently about “settle?”
Interesting. Have a source? Google translate says sola means “Promises.”
sola m
genitive singular form of sols
https://en.wiktionary.org/wiki/sola#Latvian
sols m (1st declension)
1) bench
2) desk
3) settle
https://en.wiktionary.org/wiki/sols#Latvian