Cleaving: Are a horse and rider "adjacent"?

[paradox42]

I allow (Great) Cleave and WWA to work on swarms. WWA is really simple: roll once to hit swarm AC, if you do, roll 1 damage at 150% (as if an area attack) and inflict that on the swarm. Easy. Great Cleave I'm not as set on how to adjudicate, I'm thinking of just allowing it to ignore the half weapon damage of some swarms and do half weapon damage to swarms normally immune to weapon damage, but I don't know if that's the best way to do it.

Love these rules! Yoinking them for my own use (someday- not running a game ATM but may be soon).

For some reason it's giving me the "You must spread XP around before giving to SotS again" message, even though I haven't given SotS any XP in months. Weird.