I think there were lots of doubts there - in many of the sons of Feanor. Yes, they stood by him and took the Oath, and yes, they followed him to Alqualonde and murdered many to gain the ships, but I don't think their hearts were really in it - at least not the older sons. No matter what, though, it was a horrible time and they were, without doubt, following an elf who was borderline insane.

- Erulisse (one L)