doc fix

nifty5/multi_field.py

@@ -228,11 +228,9 @@ class MultiField(object):
         Parameters
         ----------
         fields: iterable of MultiFields
-            The set of input fields. Their domains need not be identical,
-            but they must not be incompatible, e.g. by having different
-            DomainTuples for the same key.
+            The set of input fields. Their domains need not be identical.
         domain: MultiDomain or None
-            If supplied, this mjst be the domain of the resulting field.
+            If supplied, this will be the domain of the resulting field.
             Providing this domain will accelerate the function.
 
         Returns