Basically in a nutshell my question is fairly straightforward. The higher your armor skill is (in light armor, or heavy armor) the higher the defense is on light/heavy armor, correct?

Just wondering, because I have 100 heavy armor and very little in light armor. My follower uses light armor (brotherhood initiate) Since I'm lvl 60 I dropped lydia. The problem is I can't calculate what the overall armor rating is of what I'm giving my follower in terms of light armor.

It should be way higher than what I can actually see due to my low-level light armor skill rating right? Sorry if this is a newbish question, I haven't played this game in forever.

I don't think armor skill actually affects the displayed armor rating. I think it just adds a layer of damage reduction in there, but you'd have to ask one of the more technically astute people about the details.

Skill - is - reflected in armor rating.

Correct, the higher your armor skill, the higher your armor rating gets.

"displayed armor rating = (worn armor rating + item quality) * (1 + 0.4 * (skill + skill effect)/100) *
(1 + Custom Fit or Well Fitted + Matching Set) * (1 + Agile Defender or Juggernaut) +
(shield armor rating + item quality) * (1 + 0.4 * (skill + skill effect)/100) *
(1 + Custom Fit or Well Fitted + Matching Set) + armor effects
hidden armor rating = 25 per piece worn
damage reduction% = (displayed armor rating + hidden armor rating) * 0.12" http://www.uesp.net/wiki/Skyrim:Armor
Hope this helps.