Ambush scenario from "Chaos on the streets"

Hi

How do you interpret the "taking off the board" ending conditions of the "Ambush" scenario from "Chaos on the streets? The text says:

ending the game

Do not roll for Rout tests during this game. Instead, the game
will last 10 turns or until all the wyrdstone shards have been
carried off the board, whichever comes first. The warband
that gets the most wyrdstone shards off the table (or held by
one of its Heroes when the game ends) is considered the
winner.

Does this mean that the defender can win by simply racing his shard carrying heroes to any table edge and simply leaving the board?

I'd be curious to know how others are seeing it

Cheers,

Just out of curiosity, how else could it be interpreted?

Having played the scenario around a couple of hundred times in 17 yrs it never seemed all that simple to leave the board with other warbands trying all their tricks to stop you. We have had warbands that just crushed all the attackers on occasion, but that was an unusual circumstance as opposed to a grand strategy.

Hi
The reason for this question is that it seemed too easy... Until I actually played the scenario.
Now I know it is damn hard to take the heres off the board with other warbands closing in on all sides.
Cheers,

Amen.

We had one player who would just hole up and fight every time. He was amazingly lucky at it, but I wouldn't recommend it as a consistent strategy. I tend to bleed henchmen at an alarming rate whether I run or fight.