Offer sheets are not going to work on players like Hammilton and Saad unless they are max amount offers and that is a steep steep price to pay for one player without even considering the retalitory offersheets that will come back some day.
Personally I believe the Retaliatory aspect is over blown. Bear with me, Im going hypothetical with this so don't worry about the salaries and names too much. Im going to use Nyquist and Hamilton as an example.
Lets say we sign Dougie to 7.305 million dollar offer sheet. Bruins decide they can't afford that/Dougie isnt worth that. They take the two 1sts, a 2nd and a 3rd.
Now out of spite the Bruins turn around and offer Nyquist 5.477. We let him walk and take Boston's 1st, 2nd and 3rd.
We effectively traded a 1st and Nyquist for Hamilton. Is Boston's retaliation that big of a deal? Would you guys be okay with this type of swap?
Even if it doesn't make perfect sense with these two players and the salaries I picked, this example shows that the retaliatory threat can be circumvented (to some extent).