Twin Drills
topic #7929 discusses twin drills and twintails, and the conclusion there was that they could be one and the same, however, doing a search using (twin_drills -twintails) shows that some posts do not tag some twin drills as twintails (e.g. post #2118025, compare post #2186490).
I've updated the twin drills wiki to illustrate the distinction as outlined in topic #7929.
Twin Braids
topic #2986 discusses twin braids and twintails, and the conclusion there was that they are not one and the same, however, doing a search using (twin_braids twintails) shows that some posts tag some twin braids as twintails (e.g. post #2120330, compare post #2222454).
For a similar set of examples of twin braids and twintails as illustrated in topic #7929:
Twin Braids are Twintails: post #743124
Twin Braids aren't Twintails: post #1892901
Twin Braids & Twintails: post #2173829
Conclusion
I'm more for the using the distinction as outlined for twin drills to be used for twin braids as well. People could still search for straight and only straight twintails by subtracting braid and drill hair in the search query.
I believe this distinction should be standardized though, one way or the other, and so want to hear what others have to say on this.