Z: It includes two singular items as an abuse as well via "common sense" rule appliable to everything, depending of the whim and mood of the one who is calling the shoots. If the subject somehow catches Mur's interest, and we get a concrete case of this, I doubt that the accused one would succeed to explain to Mur that the deed wasn't cheating, and that two separate items/morphs/whatever are a whole different matter.
MD perspective is that we should try to prove people aren't alts, rather than proving they are alts. I'm not assuming is this right or wrong, just that it is so.
http://magicduel.com/page/Announcement/view/1214
This internet caffe and student campus thing is quite eye catching in that direction, I'm not sure is the same thing applied to regular alt checker system, if it is then it is clear that MD is preventing advantages of having an alt on the expense of the possibility of people encouraging their close ones to play MD with them.
Maybe I'm jumping with the conclusions too much, I need to get some infos on that alt checker, but I felt it was implied it used whatever means it could to connect two players.
No adepting, no attacking, no trading... Etc. Basically, you want an alt, you have to cut it off from your other character as much as possible, no interaction, that's the way I see it in regards to MD rules.