Yes , they dropped the wire size when they came out with the dual fans..but they under-estimated the current draw . They later changed the wire feed and also changed the fuse rating on low fan relay from 15 to 25 amp. [ the ones w/fuse on top of each relay]
Some guys in Tropical Climates take that same feed wire from the low relay to the R15 and use that to trigger another independent, higher amp circuit with another relay, which by-passes the R15 circuit altogether, allowing for High Fan for a/c condenser airflow. No need to change the wire from the 1.5 size b/c that now only feeds the coil side of the new relay. [ Low amps].
Never tried it, but I can see the advantage of a high fan for cond. airflow when one has the extreme thermal load conditions of Tropical type climates............................which lately, could be almost anywhere in the USA ...
Maybe we should just call that one the " Global Warming Modification TSB" ???
Here is the latest proto-type we are working on ..definate solution for
any Global Conditions , right into the next 10 years..

http://www.sl113.org/forums/uploaded/cees%20klumper/2005621181316_airco1.jpg