Can't count any other bonuses, they are always in addition to the minimum. So... null. Minimum is supposed to be maintained regardless of tactics or party composition. You can't prove it isn't needed when the system designers say it is for the system to work as intended. The moment you bring up "Warlord bonuses" you've actually proved you don't even understand all the facts behind the issue. And that is all you've proved.
Also, did you play at Epic? Because characters who started with the minimum, at epic, go down to 35% chance to hit vs even level if they don't happen to have class bonuses. Elites: 25%. Add four levels for an E+4, 5%. Solo.. oops, another defense boost. You can literally get to the point where an E+4 solo requires a 20 to hit, not crit, and even with CA you crit on a 20... but miss on a 19. Not that this situation was terribly threatening with MM1 monsters, you just whacked the thing till it died anyway, but it wasn't intended to be possible at all.
The minimum exists for a good reason. Expertise is the only way of maintaining the minimum (nearly, anyway, every ED should have a stat boost, a reroll mechanic, or a flat +1 to attacks, or something powerful enough to compensate for not having it, but I digress).
And yes Guileful Switch was errata'd, you can now only use it as the first action on your turn, so no more double-turning.
I very strongly disagree with the part I bolded... Honestly, if that's what the designers intended, then I can only say that (not surprisingly) I also strongly disagree with their views on how the game should work.
If the game is supposed to maintain the same exact chances at all levels of play, I don't see the point in having levels. To me, it makes sense that Epic Threats would be more difficult -and require greater teamwork- than lesser threats.
To answer your other question, yes, I did play Epic. I've gone from 1 - 30 many times. I never once experience what you are suggesting whenever I had a character which I built within the reasonable expectations of the game. By this I mean that I started with stats in my primary scores which the game suggested I should have.
In my eyes, having different resources at those higher levels do indeed matter. Even if I'm not counting bonuses, having a power which targets Will or Reflex instead of AC (for example) is a big boost simply because those are (typically) easier defenses to hit. This too is part of what I mean by better tactics - knowing your enemy.
Like I said, I'll search for the old thread in which I had this conversation before when looking at MM1 vs a Character without any bonuses. I have been looking; it's just taking a while because it was several years ago. For now I'll concede that -if you're not allowed to factor in any of the party's resources- the feats were needed when facing opponents four levels higher.
Best case scenario, let's say you're 100% correct and I am 100% wrong. That still ends up being somewhat shoddy design because it does in fact mean you need to choose this feat. Meaningful choice has been removed from an area of the game where choice is supposed to give the player freedom to mold their character.
Even if the feats aren't needed, they still end up being no-brainer choices simply because of how much they boost a character's power. This is actually something I can comment on from a current campaign. I'm playing a Warlord; the party also has a second Warlord in the party. I chose Expertise; the other player didn't and instead went with more flavorful choices (which, normally, I am very much in favor of when not playing D&D.) He also chose a weapon which has less of a proficiency bonus than mine does. We both have attacks which grant bonuses and healing to the party; I hit far more often... needless to say, even though I do not feel I *need* the feat, seeing the difference in what amount of power I contribute to the party with it as opposed to without it makes me choose the feat every time.
To be sure, and to go back and press upon my point again, I do in fact believe there are flaws in how 4E is built. I in no way disagree with that. However, I do not feel that Expertise feats were necessary; other options (which include prompting players to be a little more thoughtful when combating tougher foes,) I believe, would have been far more satisfying to fix some of the issues.
Real quick though, let's assume you really did need a 20 to hit, and, out of curiosity, see what happens if we are allowed to factor in party resources. Flanking brings that 20 to an 18; aid another can be used to get to 16; I'd be flabbergasted if somebody in the party didn't have something to at least give a +2 bonus to get to 14, and I'd also be highly surprised if the creature didn't have one defense which was a point or two lower than the others... let's say 13 to be generous to the monster. Keep in mind, this is 4 levels higher than the party. Oh, and lest we forget that one of the new design changes was the remove some of the defense boosts to solos... hmm, weird.
I can hear the response now "but that means some members of the party need to use their turns to help somebody else instead of getting to do something." Um, well, yeah, I thought that was the point of how 4E was built? To work as a team. Also, weren't we talking about a solo in this example? A monster which is supposed to be equal to five creatures? Yet it seems odd that it would take multiple characters to effectively combat one? Not to me..
So, what's the alternative? Well, let's give out expertise; let's make the defenses of monsters easier, and on top of that let's still allow characters to keep everything they had before too. "Solos suck! They die too easy! They can't challenge the party." One of the biggest complaints against solos had been economy of actions; hoever, looking at my first theoretical situation, the problem was shared by both sides of the fight. The solo has only one turn; the party had to pool their resources together to combat the solo... seems balanced to me.
