原來是這樣的問題呀!
Parameter : Different options for parameterization of the result and fillet surface
Default : Internal computed best filling parameterization
Patch 1 : Parameterization is taken from the 1st patch
Patch 2 : Parameterization is taken from the 2nd patch
Average : Average of parameterization from patch 1 and patch 2 is taken
Blend : Traces have parameterization of their correspondent surface