mfr02

When binding on a 2G4 system, the receiver "learns" the code for the transmitter that it is being paired with. Each transmitter has its own identity. Since the binding procedure inveriably needs hands on at the receiver, swapping remotely is not a viable option. The basic idea of 2G4 is that any one receiver will only respond to one transmitter until it has been re-bound to the "new" transmitter. Swapping transmitters mid-session would require a srcond, matching, receiver and the ability to swap between them either remotely or auomatically. Something I was used to back in the early days of electronic telephone exchanges, not something I ever cared to go into on a model, where space and weight (not to mention cost) count a lot more.
In the days of VHF/UHF radios running on crystals, as long as both transmitter and receiver had matching crystals, it was easily possible to switch off one transmitter and fire up another and carry on. The downside to that was that if the intended transmitter was further away from the receiver than another transmitter on the same channel, a thing called the "capture ratio" came into play - the new, unintended, transmitter would win and start controlling. OK if intended, less so if not. One one lake local to me, the club organised "relay races" to get yachts round the island in the lake where the ability to swap transmitters was used in full, usually involving a lot of shouting and waving at the next skipper.. Today, with modern equipment, the actual transmitter would need to be physically handed on.

Hydro Junkie

You could get away with twin transmitters but, to do so, you would have to have twin receivers and battery packs in the boat. You could use the same servos for both receivers, just put in a "Y" adapter between the servo and the receivers. The one drawback to this would be you would need to set up a switching system to turn the unused receiver off to prevent the two from fighting as one is in failsafe while the other is trying to operate the servos

Got RPM