A spokesman for Philips software in Palo Alto, California had this to say when I queried him about the Marantz RC-5000 being able to learn the Pioneer Elite high frequency IR:

"That information regarding the RC5000 is absoluelty false. That piece is
an OEM version of Pronto and has the exact same functionality as The Pronto,
just a different color. Philips Digital Entertainment developed the Pronto
exclusivley, and OEM'd it to Marantz."

I have a Pioneer Elite 16x9 projection monitor, and was unable to get Pronto to learn the Elite remote. (The Elite frequency is something above 1 megHz.) However, I got an older remote from my dealer and Pronto was able to read some of the IR controls. I still have been unable to change the "screen modes" with Pronto. So, I use the Elite remote for that function, not exactly a step forward. The Philips spokesman said the next generation of Pronto software should enable Pronto to learn the high frequencies (i.e, above 56kHz).