In Justin Blackmon's case, we wouldn't be as confident. Tania Ganguli spoke to someone familiar with Blackmon's negotiations who wasn't so sure he would be in camp on time.
Griffin's deal lacks "offset" language in the contract that theoretically can protect a team if it cuts him from a guaranteed contract and he signs elsewhere. The Jacksonville Jaguars seem likely to look for more protection in Blackmon's deal because of his recent DUI arrest. It only makes sense that would hurt him at the bargaining table.
While most rookies in this new CBA world get easily solved McContracts, Blackmon's deal is a little more complicated.