Hellcat –
You Asked.
I think I answered in depth, concerning the royal gifts - they are not linear in this fashion:
Due to the way they are transferred (a tale in itself) the gift will be "spread" between all direct descendents of the first forbear who swore oath to the Fellowship. It will not "pass" in equal measure: but like water flowing downslope, will "choose" the easiest route. Descendents with a natural tendency toward this trait in their character will "inherit" more of the gift than ones who naturally bend in another direction.
Further: the more descendents there are to "spread" the gift through, the less defined the inheritance…in some, it will be more pronounced, in others, not prominent at all.
Where there is only "one" descendent, the gift will fall to that one, and be expressed with virulently full force, no question.
This is why the line of descent varies, and why the Fellowship name the successor of ROYAL LINES always, without exception. Caithdeinen are Fellowship Named only in times when the royal line could fall into jeopardy and crown rule might fall to the shadow behind the throne. (see passage referring to that in Fugitive Prince when Jeynsa is named to succeed Jieret).
The royal gifts do NOT transfer to caithdeinen in case of failure of a lineage.
Therefore the degree to which a royal gift expresses is twofold: inherited potency (how many descendents there are who could "carry" the trait) added to personal CHOICE and CHARACTER: how is each individual inclined toward that gift in the first place.
In case of one descendent, but a character not inclined - you would see the gift express, but you would see the one in descended lineage at odds with its drive…there would be internal conflict with that gift…not a good situation.
In Arithon's case: his character is in accord with the gift, AND the gift, unstoppable as he is the only one living bearing the lineage.
In the case of Lysaer's father: given the man's extreme hatred, and the longterm erosion of his character in the course of a truly (you have no idea) BITTER feud: the gift of s'Ilessid justice WAS at play, or Arithon would have died in a messy way, rather than have been sent through the Gate as exile.
On your second question concerning Davien's being rendered discorporate: not much has been said about this. Many of you have "jumped to conclusions" as to the why and the wherefore of what happened. Davien WAS rendered discorporate by his colleagues…this was not done as "punishment" as many of you have supposed. Alot (ALOT!!) more was at play, and, at stake at the time…and it will unfold in due course. It's too wrapped up in what you see as the enigma behind Davien himself…and beware what you suppose in this case. Every speculation I have ever seen from readers, in Davien's case, has been wrong…colored by what you "suppose" the reasons to have been.
To explain why the Five Centuries' Fountain was guarded would give away too much - suffice to say this: the Fountain was a test of sorts.
The escape of the shadows happened at the time of Davien's being rendered discorporate. The six Sorcerers did not know it would happen.
More I cannot say - it will unfold in due time. You will see more of Davien, and will BEGIN to unwind the very first strand of his motivations in Traitor's Knot.
There will be MORE…I don't expect this subject to quiet down until said is done, and Arc 5 is fully complete.