or shorter and for multiselection:

// config: norepeat noautolaunch
function sTrSrf(){
var objs = moi.geometryDatabase.getSelectedObjects();
var factory = moi.command.createFactory( 'shrinktrimmedsrf' );
factory.setInput( 0, objs );
var xxx=factory.calculate();
factory.cancel();
moi.geometryDatabase.removeObjects(objs);
moi.geometryDatabase.addObjects(xxx);
for(var i=0; i<xxx.length;i++)xxx.item(i).selected=true;
}
sTrSrf();