Well, if I was you I would not. First because there is a strong chance that you will not get the bonus and second because if you do get the bonus people gonna complain and youll end up getting reported
Well obviously there's a risk, it's not available to level 19s. But even tho you managed to do it, if you level past 225 and try for the next rank in Master of Anatomy - Spell - World of Warcraft there is a chance it will give you nothing because it requires level 25 to have. But then again, there's always the chance that it will work and you'll get 3 extra crit rating.
Worst case scenario, you have to relevel skinning.
You won't get the bonus my former level 19 rogue had 450 skinning, which at one point was possible without exploiting, the buffs have a level requirement now tho.
i had 3 twinks with over 225 mining, i wasn't paying attention and after 4 darkmoon faires it seemed like i was missing something and it was 7 stam on each. they had all popped to 300 doing the DMF profession quest that add +5 each time DMF comes up and lost the mining bonus at 225 and could not use the 300 mining bonus due to a level-req.