"While physically present" (note the ADVERB is being challenged, not the adjective). Hyphens here are ungrammatical. We need some quality citations at least, but I suspect it was an editor's error. Equinox◑ 21:20, 6 September 2012 (UTC)
A question from ignorance: Why are hyphens ungrammatical in the adverb but not the adjective? Furius (talk) 02:31, 7 September 2012 (UTC)
@Furius: An adjective use of a multi-word term can make it difficult to determine how to group the words, eg, "baked-apple dessert" vs "baked apple dessert". The former is less ambiguous than the latter, which could be any "apple dessert" that was "baked". This is less likely with adverbs and predicate use of the adjective.
@Eq: Based on a review of some Googles Books usage:
face-to-face looks 10-20 times more common as an attributive adjective.
The two forms seem almost equal in frequency as predicate (after forms of be).
So the relative commonness of usage in this set of edited works supports the grammar/clarity argument, but the predicate use makes the hyphenated form less than universal for adjectives. DCDuringTALK 03:19, 7 September 2012 (UTC)`
Really? This is just a question of whether or not it is an alternative form of the adverb. The relative frequency numbers would seem to settle it, unless we are going to get all prescriptive, which is far from our style. DCDuringTALK 01:54, 12 September 2012 (UTC)