X3 you've got to loop them.
To me, looping the transmission "COOLING" lines would be the equivilent of looping the radiator hoses, it's never a good idea to take the cooler part of the equation, wheter you "THINK" you need it or not.
If your tranny is only running 180 degrees then think how cool it would be if you did have a cooler? You might not even have to change the fluid then? It for sure would last longer, it only takes a small cooler to do alot of work and IMO installing one would be, by far, one of your better investments.
JM> 2 cents, Cp