All I can say is every instructor teaching everything there way, so what may be a simple block to other maybe something totally different for someone else. I know when my instructor teaches all mhe say is I teach TKD now whether the moves are truely TKD who really knows, but the concept is. I wish some people here would remember that TKD was not anything before they named it and then it became TKD. Also on the same token here so many art infuenced each other and so many instructor teach differently and add a nd delete certain techs to fit there needs, just like all of us. Joint Locks was part of the training when we was station Korea around 1968 or so and again when I was there again in 1978 and again in 1994-1998. The last time I was there was 2003 and it was alot of Olympic going on but you could still find people teaching the older version I know. I will not call it Traditional because that always opens pandora's box but will say the version I learned had joint locks and throws.
For the original question we try to show two or three variation of each techniques to givethe students that additional in sight to try and expand on each and every technique so there journey will grows as a whole.