After reading Sdaji's posts (and a bit of Dawkins) I must say that I have changed my tune on the topic of crossing sub-species. I would like to say from the get-go that I will not be doing this but here is my reason why.
These sub-species have evolved in different locations according to a number of environmental cues that favoured particular attributes, the end result is the wild type looks that have, in recent years, become a bit passe. The morph market has gained traction and is developed through favourable breeding of bright colours which is contrary to the environmental drivers in the wild. Further to this, the increased reproduction rate of captive pythons compared to wild pythons and the large control keepers have over which pythons breed has accelerated this change. End result, even in the short time that we have been breeding reptiles we have created a significant divergence from wild populations negating our ability to release them into the wild. To consider the pet reptile trade as a 'backup' for preservation of wild populations is ludicrous given the afore mentioned divergence.
The drivers behind the evolution of captive bred reptiles are based on aesthetics and robustness. A percentage of new keepers will be looking for something different to display in their living room and this market will be met with subspecies hybrids. The market for species and locality pure animals will not disappear nor diminish, the hybrid market will simply be one of the growth areas in the hobby along with the morph market. If we remove current restrictions on crossing subspecies and allow this market to develop then there will be an increase in the honesty of an animals history (why bother stating an animal is pure if you can sell it as a hybrid for the same amount). This has already occurred in the Port Mac carpet market, rather then people selling them as pure Diamonds, they now have an acceptable label to put on them.
As a final point, I think some APS members are guilty of thinking that APS represents a good sample of people involved in keeping and breeding reptiles. This simply isn't true, there are vastly different opinions and values held by keepers out there. You only need to consider the fact that there are 15,000 people actively keeping reptiles in NSW and compare that to the number of members. There are occasions where our finger is not on the pulse.
As I have previously stated, I will not be crossing sub-species. I do however feel that it is likely to be a foregone conclusion that this will occur.