I think the assistant bears the majority of the load of ID'ing recruiting candidates, and sealing deals but the Head Coach swoops in where necessary to seal the deal with the most desired targets.
With that in mind Hak's successful track record in recruiting should provide some security that he will continue to land top flight recruits.
The wild card would be, and I'm guessing here, that the Head Coach has input into who the recruiting targets will be, and by presence alone provides motivation for a recruit to commit. Blais absence indeed leaves a void which may or may not be an issue in the future.
I'm guessing Hakstol has enough experience and success here that we don't need to worry too much, and certainly don't need to lose sleep over the doom that a poster named "State of Hockey" might lay on our program.