Trading away a bonafide top6 centre in his prime and under contract for 5 more years at $5.25M is certainly a unique way for a GM to quit his job.
Jets are trying to stay 850k under the cap this year for Perfetti's bonus. Every dollar of that bonus that doesn't fit under this year's cap applies to next year's. McGroarty becomes 2c for the Jets next year too. Doesn't make sense for either team.