One thing I'm not sure I understand is what it means to have to wait a full three seconds to repeat a button press.
I don’t even understand what having to wait three full seconds before repeating a button press. I’ve never seen that and I’ve tried to replicate as many ways I can think on all three of my DVRs. I hope the OP can clarify that one because I may correctly understand the issue. It might be why I can’t replicate it.
I apparently missed what you're referring to, but it might have to do with an issue I've seen with the HR23-700... namely that it can be hard to change the channel (among other things).
You essentially have to wait so many seconds in between hitting a number before hitting another one... and in so doing, the HR23-700 often "times out" prior to hitting all three numbers... and don't get me started if you're trying to change the channel to an OTA channel with four button presses!
It can also be a pain when you're going through the Playlist or the Guide as well as many other menu functions.
However, I am PROUD to say that this is now GREATLY improved with the newest NR.