Wondering about the necessity of editing this specific question: What technique is Eddie Van Der Meer using?
...the OP originally asks about a specific technique starting at 0:21 of the video he posts in the question. I answer about and several others comment on the technique he is pointing out (a thumb slap.) The OP even mentions that he believes the technique to be a thumb slap...
For some reason, the OP edits the question to point out an entirely different technique at 0:25 of the video (the technique is Rasgueado.)
I have edited my answer to better correspond to the OP's edit but, the comments, and arguably part of the question itself, no longer makes a lot of sense...
In a case like this, is it pertinent to edit back the original time the OP was asking about and then add in the bit about the other technique at the later time?