We know thatb
Amex MR -> CO, Delta, US (1:1) or 1 SW RR/1250 points
How about if we convert
Amer MR -> SPG (1:1)
& then convert
SPG -> AA, Alaska, Alitalia, AW, BA, Lufthansa, NW (1:1)
Woud this successfully convert Amex MR to SPG to AA, AW, BA, NW, Luftthansa & Alitalia