Spell Effects on Beginners Luck?

What effects, if any, do spells like Strength of the Ox have on Beginner’s Luck?
As this spell adds dice directly to the Power Stat while it is sustained does it then make it easier to learn the Brawling skill by both lowering the aptitude as well as raising the root skill to open it with?
Presume a power of B4 is Raised to a B6 everyday by a wizard who sustains and maintains this spell as an instinct.

I don’t think I’d alter the aptitude for a temporary bump. You’re more likely to hit those doubled Obs. I think that’s enough.

If he uses the spell to try to break down a door or lift a heavy object we compare the total dice used to the obstacle of the task to determine the type of test received.
If he uses the spell to bump his Power up to B6 so as to be able to throw two helping dice into the battering ram being wielded by the party against the Ob5 Sturdy Wooden Exterior Door he earns a Difficult test, where as if he would have used his normal Power of B4 he would have earned a Challenging test. That’s pretty simple to figure out from the rules.
Beginner’s Luck however, not so much. On the surface it would appear to follow the same logic, the spell boosts the stat and the (now boosted) stat determines the number of dice rolled, shade of dice rolled, apptitude of learning and root of new skill.
Once opened, a skills root is no longer dependant upon its root stat but operates on its own merit, (raising or lowering a stat has no effect on the skills already learned that are based upon it) so logically, opening a skill based on a boosted stat, the skill would open at the higher root because when the spell was canceled it wouldn’t be any different than if the character had suffered a loss to his Power stat (perhaps from a spell that taxed Power).
But I have no idea how Luke and company envisioned it to work.

It’s an interesting thought, but I think it’s wrong. Roots and aptitude are based on the base stat, the thing written down on your character sheet as the permanent value. Wounds, tax, and magic enhancement don’t change that.

So the magic effect can add dice to help you perform a task but the aptitude for learning as well as the skills root stat when learning is all you (the mage in the example would be using his B6 Power (B4 + 2D for his spell) to pass any Brawling situations he found himself in but his Aptitude remains at 6 and when he opens the skill, he would do so at the root of his B4 Power (skill opens at B2).
So in effect, he loses a die of brawling once the skill opens even though he is still using the same spell because he is now throwing B2 dice at normal obstacles instead of B6 dice at double obstacles? That seems wrong to me.
But I suppose that, in the fiction, once the character started realizing how to do things on his own instead of just relying on the power of the spell he would start limiting himself as he is now actually learning something about the skill.
And how many times have we read stories where the hero with the magic fill in the blank has to overcome odds and discover his own ability once his fill in the blank was taken from him.
I’m sold! (Thanks Guys)

On the flip side, you don’t change your aptitudes when your abilities are reduced because of injury. As noted by Shaun, if you’re getting a bunch of bonus dice, you’ll already be shifting the range of tests that count as routine, making it more likely to earn them. Doing that and shifting the aptitude down would be “double dipping” as we say.

Dice from spells like Strength of the Ox are advantage dice. As such, they do not change aptitude or affect roots.