Well that may be true for some paladins, but considering all the adds on this tier of content come out at very specific predictable times, I just have an avenger's shield ready for them when they spawn, or even use one of my 2 taunts. Theres never really been a time where I thought to myself "if only my judgement had longer range I coulda picked up those adds" after spending over 70 levels without the range boost.

I thought your information very helpful. I am a new player and it seems I've been misinformed on how to play a prot paladin. Currently I am having issues with holding aggro. I have reforged everything like was stated above and it seems like my ability to hold threat decreased immensely. Before, I had some of my stats reforged to Expertise, and now everything was reforged to balance out my parry/dodge. For some reason, I'm missing something in the reforging area. Any advice would be greatly appreciated.

By the way, my paladin is Faction from Eitrigg.

I won't say I'm an expert on protection paladins, but I will give you the same advice as I gave a friend of mine.
You can hold aggro easily even with 0% hit and the base 10 expertise from the glyph (get the glyph of seal of truth by the way, since I see that you do not have it).

I would say it is a matter of the openers you use at pulling, a 3 holy power shield of the righteous at boss mobs will shoot you ahead of everyone on threat.
On multiple mobs remember to use inquisition and hammer of the righteous.
You can use divine plea to get to 3 holy power for the start of a fight.

Also I would suggest to change your talents a bit, eternal glory is useless for protection, as is improved hammer of justice.
I rarely use hallowed ground either, except just for consecration and dps show off on multiple mobs
Instead you could use those points on improvement judgement and rule of law, also I suggest to take pursuit of justice.

Also check the first post of this thread, you will see the talents and what each affects.

Because Maintankadin maintains a thread on Prot Pally mechanics with numerical analysis of all the "why" answers, this thread simply summarizes them.

For example, https://sites.google.com/site/matlabadin/4-3/43_CT.png summarizes talent DPS nicely. Talking about why some dps talents are better than others is less useful when you can just point to the graph.

As for your specific question, theck's thread about talent choices says: "Eye for an Eye deserves a special mention here. It seems to proc off of most spell-like attacks, regardless of damage type (even physical). Thus, depending on the boss, it can contribute anywhere from 1%-3% of your DPS completely passively. I personally value the utility of Improved Judgement too much to make that trade, but for those that don't E4E is a perfectly valid way to progress to tier 2 of Ret."

Holding up an Avenger's Shield is not really an option if you want to maintain higher dps, and the fact that Judgement allows you to refresh your SoT stack at range during movement phases has frequently gotten me dps gains. It's a quality of life thing, but Eye is a valid talent...just don't dismiss the utility of Imp Judgement.

I got a new UI today(Elv UI), if any one else has this or has had this problem maybe you can answer this. As far as I knew you shoot the 102.4% because for every level past 85 there is the penalty to doge parry and miss. I was playing around with the UI and noticed at the bottom there is an Avoidance calculator. Right now with no Raid buffs I am sitting at 105.5% which is what I personally calculate, and what the UI addon shows.

When I target a Boss target dummy the number drops 2.85% down to 102.65%. Unless there is something I am overlooking this seems wrong, because that 102.4% was supposed to cover that accomodation for the bosses level.

To me, it seems that what it's doing is calculating in the penalties to avoidance to my percentage, so in theory that should make the block cap 100% to my UI. But, I have played around with it, taking off a piece of gear so that on my UI my avoidance falls below 102.4%. When it is both above 102.4% and below, there is a Unhittable: calc. When the UI shows my avoidance at 102.65% it says, Unhittable: + .25%, so meaning I am .25% over the cap. When I take a piece of gear off and it changes to 101.87% it says Unhittable: - .53%, so I am below cap. So it seems that it is still using 102.4% as the cap, even AFTER calculating boss penalties.

Does anyone know if this is a fluke, or there is some additional element to being hit by a boss we are missing?

Your total combat table coverage should be 102.4%. Once you factor in the difference between you and the raid boss, it'll effectively drop to 100%. Assuming your character is max level, any program that says differently than 102.4% to start, then 100% adjusting for a boss, is wrong.