Fëanor's Death, Convenient?

[Saurreg]

Feanor indeed was the mightiest of all. But if he lived, he would have probably made war between the noldor and sindar. And if that had happened, perhaps the sindar wouldn´t help the noldor against Morgoth.

I cannot recall an instance in which the Sindar of Doriath officially aided the Noldor in the War of the Silmarils. The first battle of the stars was fought before the Noldor returned to Beleriand and hence cannot be counted as such.

During the fifth battle, only Bereg and Mablung joined Fingon, Thingol would not give the Noldor aid in strong arms again.

Sindar whom dwelled with the Noldors and served under their banner are of course excluded.