Is it OK to copy Blizzard functions and hooksecure their function with tweaked copy?

[Nikita S. Doroshenko]

I want to change Blizzard's function FriendsFrame_UpdateFriends() to add my buttons in to each frame of long scroll-able list of friends.

So i made hooksecurefunc("FriendsFrame_UpdateFriends", FriendsFrame_UpdateFriendsCopy)

FriendsFrame_UpdateFriendsCopy() is copy of FriendsFrame_UpdateFriends(), but with a few new lines of code.

Is it OK to do so, or is there better way to bulk change each frame of long scroll-able list? because i think hooksecure function is not same for future proof (for future updates).

PS I tried to make for loop for this scroll-able frame to manually attach my buttons in to each frame of scroll-able frame, but this buttons looks hardcoded, and i can't controll them regardless of hidden parent frames parameters that are only available in FriendsFrame_UpdateFriends().