They are U spells in previous RM versions (no RR). So, aside from a sneaking suspicion that they just didn't think about the possible ramifications of changing them to an E spell in RMU, it would appear the spells are not intended to be resistible... well, aside from the creative use our group made of it. That, I think, would have justified some kind of roll to avoid it (even if it was just a Agility or Tumbling check).