They should be trying to work out a sign & trade with the Raptors involving Lin instead of giving up Shumpert to get Nash IMO.
Toronto is obviously high on Nash but they're also high on Jeremy Lin, & they just invested a ton of money on Lin's BFF Landry so I can't imagine they'd be opposed to giving up some of their assets along with Jose Calderon to the Suns to get Lin to Toronto.
I would much rather try & swing a trade like this over giving up Shumpert to obtain Nash:
Knicks sign & trade Jeremy Lin & Landry Fields
Knicks get Steve Nash & Sonny Weems
Toronto trades Jose Calderon, Sonny Weems & a 1st round pick
Toronto gets Jeremy Lin & Landry Fields
Phoenix signs & trades Steve Nash
Phoenix gets Jose Calderon & TOR's 1st rd pick
- After that sign J Kidd to a vet min contract, resign Novak & JR Smith using their Bird Rights & go after Marcus Camby with the MMLE
C - Chandler / Camby
PF - Amare / Harrellson
SF - Melo / Novak
SG - JR / Weems / White (Shump when he gets back)
PG - Nash / Kidd / Douglas