I do not use ASL 100% of the time. Most of the time I do not understand that language but if I can "hoof" it, it can be communicative. I am from the "old school" English sign language which I would sign just about every word I say instead of abbreviate like ASL or "over dramatize" my signs. All it does give me a "glazed over" look when someone really into ASL and I would have to pick thru what they are saying. Good thing that most of the ASL folks can understand me quite well. I'm 46 and have not used much signs since I graduated from college back in 1994 so I am a bit rusty.
If you are teaching or learning ASL, go for it! Times are changing! I would say some certain words will evolve over the years that it become obsolete and some that do remember those signs would still use it or remember it.
Bless your heart in wanting to teach children ASL. I honestly did not teach my daughter sign language, wanted her to know ASL instead of my "piggin'" language LOL!