I have the following requirements:-

1. we need to have around 10 users who can contribute to a document library, mainly add,edit,delete files and folders.
2. but only 2 contributor users out of the 10 users should be able to specify unique permission for the files and folders.

So now if i check the following checkbox, then all the 10 contributor users will have the ability to specify unique permission for the files and folders, so this will not work for us.

one approach i found is that i can create a copy of the built-in Contribute permission level, i name it "Contribute with manage permissions", and check these 2 additional permission levels:-

then inside the document library I grant the 2 users this new permission level "Contribute with manage permissions".. so now the 10 users can upload files and folders and only the 2 users can define unique perms ion for the folders through the new permission level.

so i have the following 2 questions:-

1. is my above approach -of granting some contributor users that ability to define unique permission on the files and folders- considered valid?

2. i am not sure why the above approach will allow the 2 contributor users to define unique permissions for the folders only,, but not for the files?

Thanks in advance for any help.