The introgression (cross breeding) of loddigesii and harrisonniae in the last few decades have added much confusion to the ID of the recent bloomings.
Like what Big923Cattleya says, the traits are there to help. Unfortunately these traits can crossover when these two are mixed and can masquerade as the other.
TerryRos pointed out that many of the awards for either of them show some traits of both, which I can attest to in my many viewings, and can be mistaken easily for the other.
The final determination looks to be this: if the majority of the traits shows for one more than the other, then it will most likely be that species (that it possesses the most traits for) and will most likely be identified and awarded as that (and if any doubt, should be sent to SITF for full identification).
The old adage: If it quacks like a duck, and walks like a duck, then it is most certainly… a duck!