This has been updated to match my "Signature Weakness Project." I have done my best to make sure that the original content isn't altered too much, out of respect for any comments.
A fairly unusual skill weakness. Looking at the two elements, the effect and the discard condition, we get:
The effect: If you commit this to a test, you get -2 icons. If you can't discard it by the end of your turn, take 2 damage. Lather, rinse, repeat. A bit like, less annoying, and more manageable than Rex's Curse, this is a middling sort of signature weakness. possibly punishing if drawn at the wrong moment or because of an ill-timed but mostly handleable through overcommitting on a test, which Silas is kind of master of, especially on and tests, where he has good base stats. Cards that might help include Manual Dexterity (2), Defiance (2) (to kill those pesky special tokens), Stroke of Luck, and any amount of shenanigans to pass that crucial test. It's not like they won't be useful in other tests. Beware of last action draws, and you will likely be fine. Also beware of The Tower • XVI; that thing is like Kryptonite to Silas, and will probably cost you a turn to watch this thing go off anyway. I mean, Silas is a Man of the Sea, and he laughs at 2 damage at the end of his turn... once, twice, maybe three times, but, then it's into the Deep with him.
The discard condition: Pass a test with this card committed.
All in all, this is a below average signature weakness maybe as high as average at very low XP.
Box vs book It's paired with a signature asset that's pretty good, so it's up to personal preference whether you want to go with the "box," "book," or both signature sets.