When creating title tags I was wondering, do search engines see a plural title tag keyword as both a plural & singular word? IE: "Keywords" is seen as both "keyword" and "keywords"? Thanks
No they view the keywords differently. Check to see which version gets more searches and target that version if it makes sense.
It is totally a different approach according to dcristo. When you create title tags either singular or plural, just analyze it on any free or paid keyword tool on which of them were having a lot of searches.