Sqorgar, if you see my example from last page, it's that different metas / stores / player groups play at different power levels. Maybe in his group, nobody fusses about with taking infantry - why not take heroes instead, and treat it as a true skirmish game with each activating individually?
I'm not saying he took a nice list - I'm saying, the only counter to this is to be prepared to have a strong list of your own, given that in
AoS you can adjust what you're going to play during the deployment phase (or in the case of this event, during the pre-game discussion, as well).
To say that a player is "
TFG" or "
WAAC" because they bring a strong list is assigning intent, which again, I've found is a rookie mistake. In
40k tournaments, new players sometimes say this about the top players since they get absolutely crushed by them (and their very strong lists)... but I've personally found that top players are some of the most enjoyable to face (usually) because they know their rules inside and out (even if they stomp my army).
---
Now, this doesn't look like it was an enjoyable experience, but in the pre-game discussions, the
OP could:
1) Not have agreed to let the slow dwarf army be the defender
2) Upped the power level of his own list to match that of his opponent's
3) When the opponent placed over 30 models, discussed whether the warmachine crew counted towards the model limit or not (and brought over an event organizer to clarify if needed)
In a game predicated on adjusting power-level pre deployment, or even during deployment, I think being ready to do the second (adjusting power level) will be important for
AoS players going to events to have a good time and not feel they were steamrolled by an army they had no chance against.
Obviously, the opponent could also tone down his list, but since there are no clear guides to doing this (unlike a historical scenario where one side intentionally has double the units of the other, etc) the only way to be ready for this kind of situation is to be able to adjust the power of your own list accordingly to match the range of opposing armies you might face.
---
All that said, by far the best solution would be for the event organizer to somehow account for this (or at least, for real mismatches). For a friendly event, perhaps they could look over the lists and make sure there's nothing too crazy, and only allow people to field what they've listed (or less). It would be a lot of work, but it seems like this army would have easily thrown up some red flags during such a check, and the organizer could make sure it were adjusted appropriately to the event. Again, I think the AdeptiCon
40K Friendly could really give some good ideas on how to run an event like this