Yes, it's normal. No, EM isn't nerfed at all.
TF critting and ET without crit are still stronger than any other stalker attack with a full crit. If anything, I'd expect a nerf to EM and an increase in base's stalker dmg if devs cared about the stalker's AT, but I think they're happy with their "datamining" that shows EM stalkers can 2-shot a lot of newbies standing still in siren's call... 
MEH =(
Kaiser
Shouldn't stand still and explect not to be hit by any stalker newbie/non-newbies. EM shouldnt be nerfed aswell as you have said tf only crit's on one part and et doesnt even crit.
All fair in war
I was looking into the combat chat a little closer today, confused by Total Focus' Damage.
)
I examined the critical Damage it (Total Focus) did out of Hide/Placate several times and came to the conclusion only the Smash-Part of the Attack does Critical Damage, not the substantially larger Energy-Part.
I tried the same thing with Energy Punch and Bonesmasher, both do full Critcal Damage out of Hide/Placate, meaning Double Damage as Energy and Smash component get added up and added as Critical Damage.
I didn't really want to read into this, so I'll just ask here: Is it normal that only the Smash-Part of Total Focus hits Critical or was that nerfed, because ppl complained about two AS for Enery/X Stalker (I think we are nerfed enough with ET not having a Critical Strike ability
Kaiser