Somehow this post made my smile... I was reminded of "Onyxia deep breathing more often since last patch". All WoW vanilla players will know what I'm talking about ;-)
You're just unlucky. We had one run yesterday where 100% (yes, every single elite pack) had reflect damage. We all know it's RNG, but it's still fun to accuse the party leader, say that it's his fault and bully him a bit.
I rememeber a blue post saying the higer mp you play; more difficult combo's will appear and more affixes on e's also..
edit: in my experience, when playing mp6+ 80% of the e's are reflecting
This sounds extremely unlikely. I remember in a RD discussion that a blue post even said that all affixes are random and it's just about being lucky or unlucky. What is even considered to be difficult? Some people have so high LS that they don't care about RD, but other affixes are difficult for them.
Also on MP6+ there's no more RD. While farming keys/ubers on MP7/8 we had sometimes runs where none of the 5 elite packs we killed had reflect damage (and of course also the opposite, with 4 or 5 of them having RD). It's just (bad) luck.
Surprisingly, I had a run on MP4 recently where ZERO, NADA elite packs had Reflect Damage. Two had Missile Dampening, which really does nothing when I'm in Archon form. Most had Molten and Waller for some reason, which really... does not do much to me.
Two had Missile Dampening, which really does nothing when I'm in Archon form.
Great example for the discussion about which affixes are bad or not. Missile Dampening sucks for CMWW, because you don't get enough procs to sustain stunlock (hi @act 2 keywarden). Some demon hunters love Missile Dampening, because if you use Ele Arrow with Ball Lightning it will kill even nasty elites in no time (bye @act 2 keywarden).
To be honest, I only notice affixes on mp0-1 when its Reflect Damage, other than that, nothing. On higher MPs I notice all of them and it seems I am blessed with the ability to spawn Mortar elites. It is a ratio that is ungodly and the trend has seen its ups and downs but they are definitely the ones I see the most. Shielding on the other hand, I very very rarely see.