That pic is crazy man! That is certainly an issue, and something that should be fixed so that it does not happen. I will admit that I am not geared to be able to defeat any combination of affixes, but I can deal with most. Monsters that are inherently fast, then have fast as an affix, well I will try them a few times and if I cant get anywhere, I park them and move on. If I have a good open area with obstacles, maybe they are possible, but I only have 12% movement speed on my boots and they can pass me easily. I am OK with Inferno being super-hard, but damn, some of the things I have encountered might only be beatable by the top 0.0001% of the whole playing population. And that is with god gear and perfect play.
I am with you on remembering the Council and Mephisto's minions on D2. They could one shot you as well as Iron Maiden on Oblivion Knights with Gloams thrown in there as well. Before I quit playing D2 to play D3, I had a Barb that never died, get ambushed coming around a corner by a pack of Gloams and insta-death. I really hope ActiBlizz will take notice of some of the issues people are compaining about. Not the ones where somebody is crying because they suck and cant get past some part of the game, but for instances like the OP showed. One thing I liked about D2 was that a character felt very strong, even at level 42, put on an Arreats Face and equip dual Butchers Pupils, there is no doubt you could go to Baal and beat him. I am having fun playing D3, and that is in its current state of being not 100%. They can do some very good things and make it awesome, but whoever is calling the shots just does not get it.
Most of the really frustrating elite packs seem to either have at least one CC that has no counter-play (Nightmarish, Jailer, Vortex, Waller if the area is tight, Knockback depending on the build and class, ) and/or a mod that is difficult to deal with without something lock them down (Shielding, Invulnerable Minions, Fast, most abilities with a cast animation), in addition to an ability that is dangerous but can be countered or avoided on its own (Arcane, ground effects, Frozen, etc.). It seems like the intention was to get players to stack %CC reduction and offensive CC effects to lock elites down while reducing their ability to lock the player down. These mods can actually get pretty strong if you can get good rolls and stack them up, the problem is that you need at least 4-5 items to get any kind of meaningful effect, so trying to gear this way severely narrows the field of items that you can use and makes it even harder to get incremental upgrades than it already is.
This is why most players either stack defenses until they can facetank through everything, or stack damage until they can explode everything before it has a chance to do anything. There isn't anything inherently wrong with these options, but they are ridiculously expensive and not very exciting to do, so it's no wonder a lot of people are frustrated. It would be nice to have some cost-effective, or at least more interesting (and consistent) options that don't require you to overhaul your entire gear loadout.
For example, I feel like a lot more people would put some effort into learning how to use offensive CCs like %chance to freeze/chill/slow etc. if they only spawned on 1-2 item types (just weapons and off-hands, for example) but rolled with 20-30% proc chances instead of spawning in a bunch of slots with only a 1-6% chance. Similarly, if we had mods like Cannot be Jailed/Frozen/Vortexed/Frightened/etc., it'd be a lot easier to gear against specific CCs and people would be more interested in the general idea of CC mitigation.
Haven't had the chance to read through this whole thread, so I apologize if this has already been mentioned.