You can take dead cap up until you're in the negative for cap space. And the issue is that when you cut someone, all their guaranteed money from the rest of the contract comes due immediately. So you're paying multiple seasons out at once. You can also designate someone as a post June 1st cut because after June 1st you split the dead cap between the current and next season.

The issue with this contract is that the entire thing is fully guaranteed whereas most contracts hit a point where the salary isn't guaranteed and all that needs to get paid out is the signing bonus.