I can't speak to the Perdix AI as I use a Suunto AI computer. Suunto advocates that the transmitter should only be screwed "hand tight", there is no need to crank the transmitter down on the 1st stage or high pressure hose which ever the case may be. This would facilitate taking the transmitter off when transporting your gear...
....The reality is that I think the majority of wireless AI users tend to leave the transmitter in place either attached to the 1st stage (via direct connection or to a hose). I don't believe there is a correct answer and think that it comes down to user preference.
I started out removing my transmitter when transporting and eventually doing that was overcome by the laziness of human nature and in general I leave it attached to its 6 inch hose on the 1st stage. I do tend to remove it when I pack for travel to dive destinations other than the local spots near where I live, as when traveling locally by car my reg goes in a reg bag and then in the back of the car and does not really get moved between the house and the dive site, there is little chance of damage...when traveling longer distances the reg/transmitter is subjected to the higher possibility of damage in transit.
I also think that the extra high pressure hose representing an additional "failure point(s)" is grossly overstated. I believe people point to that to justify the doctrine and configuration they have adopted and put blinders on to other more significant safety issues. For instance, I have come across divers who will readily point out that the 6 inch hose that my transmitter resides on represents additional failure points but then I witness these folk diving to the extreme of their no-deco limit and sometime surpassing however brief with out any consideration, I see these same folks rushing to get in the water complacent about doing a proper buddy check. I also see these folks leaving their drysuit inflator hose attached to their reg set when they are diving wet, which would be more dangerous in the case of failure than a high pressure hose failure. If dive gear is regularly inspected and properly maintained the possibility of failure caused by the addition of an extra high pressure hose is about the same as the risk to your life diving with split fins. It is one thing to point to something as possible mode of failure but in the analysis, in reality, how many failures have occurred due to the addition of these hoses? Is the sky really falling?
-Z
