Stealing valleys is a valid tactic. Apparently you've never read 'The Art of War'. You really should some time.

Here's a hint: Less valleys = less resource production. Less resource production = fewer troops built, and more food consumed.

Even though they supposedly don't use food during holiday mode, quite a few of them will not have logged in for most of the day after they've already come off of suspension.

If by chance your opponent was already running a thin line with food, this could mean they are now up to a page or more of refuge, making them an easier target.

Tough luck on them for getting suspended.