I think this is fairly comprehensive
http://www.ansereg.com/what_tolkien_...y_said_abo.htm
other than that in a note to Laws and Customs in HoME it reports that JRRT made a comment to the effect that it would have been lawful for Beren and Tinuviel to contract the "basic" marriage described in the text (ie vows & consummation without the ceremonial feating and gift giving) IF it had not been for Beren's vow to Thingol. So I guess that is a no....
Also as Man of the Wold points out our modern eyes may read far mor into language than was intended at the time - an older but famous example is in Jane Austen's "Emma" when the vicar (whose name escapes me at the moment) 'makes love' to Miss Woodhouse in the carriage - the realtively innocent can be seen as something quite scandalous (at least for a 18th century maiden and a man of the cloth!).
Heren Istarion - an entire Order of Wizards should no so easily be led astray, surely? Don't forget that Oo la la is itself an expression that has changed sense as it crossed the channel - in France it is uttered with disapproving tones as a rule... :P