The Spell Armor (Unearthed Arcana p.51-52) states:
The caster creates ,a magical field of force which serves as if it were leather armor (AC 8). If the spell is cast upon a person already armored, it has no effect. However, if it is cast upon a creature with an armor class normally better than 9 (due to its size, speed, skin, etc.) it will benefit the normal armor class by one step, i.e. AC 8 becomes 7, AC 7 becomes 6, and so on. The magic armor spell does not slow or hinder movement, adds no weight or encumbrance, nor does it prevent spell casting(...)
Normally,a character with 16 dex + a leather armor would have AC 6, what bugs me is the ''etc.'' in the examples, I believe it is fair to say that my magic-user would have AC 6 since a comparison can be made with the real armor that it imitates, and ''etc.'' might be other examples that I'm not aware of, but I don't think the AC from dexterity is included in those examples unless ''speed'' means dex.
In the player handbook the description of Dexterity states:
Dexterity encompasses a number of physical attributes including hand-eye coordination, agility, reflexes, precision, balance, and speed of movement. A high dexterity indicates superiority in all of the above attributes(...)
So perhaps speed means Dexterity?
The spell Find Familiar also states:
Normal familiars have 2-4 hit points and armor class of 7 (due to size, speed, etc.)
So is speed just a synonym for a high dexterity score? Is there another spell (Haste does not) or buff or mention of a rule somewhere that shows a distinction between ''speed'' and ''high dexterity''?
Is my AC 6 or 7? in this case what does ''speed'' refer to?