Right.
I'd like to know: Why create these feats?
The reasons I can think of:
- Original designers canned --> it's the economy, stupid!
- Designers have decided that giving bonuses to hit is no big deal, and that PH1 feats are too weak.
- Math hole discovered; original math is off and this is steath errata.
- Designers realized high level team-tactics don't compensate for poorer to hit.
- Powercreep to sell books.
- Hitting is fun, so more hitting is more fun! This game is about fun maximization!!
- The feats are a mistake.
I choose:
[*]Math hole discovered; original math is off and this is steath errata.
This is beyond obvious to me. This is WotC shouting:
Opps, sorry. Nevermind.

Two things convince me of this:
1) The plethora of discussion pre-4E on minimizing bonuses to hit so that power creep would not get to the levels that it did in 3E/3.5. During that timeframe, the designers were purposely talking about avoiding the mistakes of the past.
2) The stealth errata for masterwork armor. With AV and PHB II, there no longer is a heavy armor AC sag in Paragon levels. Stealth errata has been done before for 4E.
The math is straightforward (all aspects of it: monster and PC chances to hit, defenses, damage, number of actions, number of hit points, and riders/conditions) and the fact that many bonus to hit powers require that the first power hits before the bonus is given illustrates the math curves and the flaw in the "synergy bonuses make up for it" theory.
There is no way WotC would have released feats that are +3 (expertise) or +4 (epic defense feats) on a D20 curve with zero conditions attached when the vast majority of the game system is +1 or +2 conditionally on a D20 curve unless they had a compelling game mechanics reason to do so. Anything else is beyond powergaming.
It is a totally different game design philosophy and mathematical model when one does this. It can only be to fix the math bugs. I find any other explanation to be customer wishful thinking that WotC knew what they were doing with the original math.