I would have guessed otherwise, if this guy is an IT pro, he probably knows to use a long and secure passphrase. I'll be surprised if someone who knows can say

I would have guessed otherwise, if this guy is an IT pro, he probably knows to use a long and secure passphrase. I'll be surprised if someone who knows can say the password was the weak point. Maybe you're right, but... I'd think the most likely way to get in would be to find the passphrase had been cached somewhere, or the unencrypted key was accidentally copied somewhere onto a swap file from some shoddily built backup process that used up most of the RAM compressing files, resulting in that or some similar leak. Same as you though, I don't really have the slightest idea.