Legion Transmog - Armor Proficiency

A recent tweet from the Devs stated that in order to unlock an appearance there are three rules that must be met:

1) The item must be bound to you,
2) You must be able to equip the item, and
3) The armor type must be specific to your class.

This means that Warriors won't be the perfect xmog farmers. While right now they can equip all the armor types, when Legion comes out they will only be able to equip plate starting from level 1.

That would have been awesome, since my Warrior just sits in her garrison doing nothing, but I'm ok with it - I love love love farming xmog. Yep, I'm weird - I'm surprised you didn't already know that.

BUT I have a few concerns.

An example is the Scarlet Mail set that I have on two toons; a hunter and a paladin.  When Legion hits, this mail set will turn into plate. Sadly, I am missing the boots on the paladin so this means that I won't have unlocked the boots since the hunter won't be able to equip it after Legion.

• I wonder what would happen if I equip it before Legion hits and leave it on her.. will it be "learned"??  
• Maybe we can talk Blizz into make the boots BOE again so I can move them to the paladin?? They are no longer available in game, and as far as I can see there are no look-alike versions.
• Do you think that Blizz will/could grandfather anything soulbound to the toons on the day that Legion hits? That would be nice for my RP toons who have some cute cloth armor that is no longer available in the game, but are on mail/plate toons.