Today I saw this question Was Textile Armour More Effective at Stopping Arrows than Mail? and my first thought was "Wow, that seems very specific and difficult to find info for".
I mean, unless this information was related in some kind of "training manual" for medieval troops1 that addressed the subject or happened to be included in the description of a battle2, practically the only way to answer would be to reproduce the armor and test it.
And, while that might be a little out of scope for the site, in youtube there are channels of people doing that kind of things (yes, really!).3
Even if I found a video from that people involving padded armour and arrows I would not be entirely comfortable posting it as an answer, because of the possibility of mistakes/inaccuracies by the producers of those videos. On the other hand, if after some time nobody answers the question, I think it would be nice at least to comment the OP about such a channel and see if he can find something that satisfies his curiosity (even by asking the channel owners).
There is any rule about it?
1 And probably, reading materials were not the best way to give training to medieval soldiers.
2 Which usually did not have that level of detail.
3 Disclaimer: I am absolutely not affiliated with any of them.