Not impossible. But who can even say how many if any?
Yes it is a cross per se, but it is trianae times trianae.
What I am saying is that if you cross a large standard Cattleya like Cattleya Pamela Hetherington ( a large, pink flowered hybrid with Laelia pumila) you might be trying to reduce the size of Hetherington, making it compact. You may be trying to use a darker colored pumila trying to introduce more color into the offspring, you might see a few. So much of it depends on the genes of pumila, the strength of those genes to reduce plant size, induce more color, OR are the Hetherington’s genes so dominate that little if any pumila traits shine through?
But in the case of trianae on trianae, it is all trianae genes. The more genes that one has in their “genetic pallete”, the more room that
Exists to produce different results.
Hybridizers spend years trying to produce specific results. Some are more successful the others. Some hybridizers may make a certain cross because both parents ‘just happen to be in flower’. That is not a plan in my mind.
The more complex the parents are, the wider that the results might be. With trianae and trianae, that is very limiting in comparison.
Trianae by trianae might be like a 4’ 10” mother making a child with her 5’ 9” husband hoping to produce a 6’9” basketball All Star!!!! What are the odds?
Again, if you really like a particular clone of trianae, why not just clone it. Don’t introduce something inferior to produce something superior.