These new 2.4 radio transmitters do operate at lower output power than the 72 band, so the current requirements from the batteries are less.

The 2.4 band (ISM frequencies) is 100 MHz wide, and is kind of the wild west as far as the FCC is concerned. Originally it was not considered good for communications because atmospheric moisture attenuated the signal over long distances. This same trait heats a lot of food in my kitchen.

On the old 72 MHz frequency channels, RC systems were limited to about a 6 KHz signal. This meant that the amount of information encoded in your transmitter's signal was very limited. Even the pulse width encoding systems were so heavily filtered that they worked at all was amazing.

My DX-8 can send 8 channels worth of data every 11 milliseconds at a 2048 resolution. That's about twice as fast as needed and probably 4 times more accurate than I could possibly detect while flying, but it shows what the bandwidth can do at these higher frequencies.

As I read the AMA note on it, I concluded the following:

1). Reflections from metal can affect 2.4 systems with multipath. Gee, it did the same on 72.

2). We need a new Technical Director at the AMA. That article was a whole lot of nothing.