What about EQ or effects as a method to manage what you hear? It'd be interesting to learn what the monitors were - as there are often big differences when changing monitors as each monitor has its own characteristic frequency response.

I should make it clear that I don't think this is some stray artefact - I think this is the way it is intended to be, it's part of the crispness when the note is struck at its fullest.
Just that - for me - it's not a welcome part of the sound.
Yes EQ does help. I was listening to the CP88 through headphones but I know from my CP5 that it will come through on my speakers (Bose L1 compacts)

Thanks for the question. One of the differences between the previous two CP Stage Piano models (CP5, CP4) and the new CP model’s is the Interface... Access to parameter controls is thought out and designed for real-time interaction. Like the reface Keyboards (mini in size only) the new CPs are focused on the access to parameters while performing. Less menu diving, more interaction.

One Knob Control
Over in our digital mixers, Yamaha has been working on compelling “One-Knob” adjustments. You turn one Knob, but are making complex changes on a predetermined Curve of settings that work! How they arrive at the settings that need to included is the result of much study. For example, say you plug an SM58 or Sennheiser 441 into a channel of your Yamaha TF digital mixer, because it has built-in EQ Curves for these specific microphones for a selection of several different source inputs... you can select female vocal, or snare drum, or whatever... the firmware recalls a specific EQ Curve (frequency selection, bandwidths, and boost/cut responses) that can be adjusted simultaneously by movement of a single Knob Control (and EQ “Super Knob”). The results the “Curve” delivers are known to work for the characteristics of the mic and the type of signal source. You choose from a array of results that all work... some you will feel work a little better than others, but they all “work”!

The result, without having to “know” how to EQ, the One-Knob System gives you varying results as you turn it from minimum toward maximum, but all the results will fall within a given range researched and known to always sound pretty darned good. Yamaha digital mixers come with these “models” for a wide range of the most commonly used Microphone inputs and Loudspeaker outputs. So that as you turn the One-Knob Control for EQ, or the One-Knob Control for Compressor/Limiters, etc., and instantly you are a sound genius — the “bad” results have been eliminated. This is where the sound reinforcement technology is now... of course on the Digital Mixers you can choose to do it manually, even setup your own settings and apply “more or less” of your favorite Curves. It's quick, it’s easy, the results are spectacular...

TONE is a one knob EQ
The TONE control found in each section of the new CPs acts as a One-Knob EQ as it is not simply more or less of one frequency, rather it is designed to change multiple frequency bands simultaneously offering the player a quick way to adjust the timbre of the instrument along a proven curve. A curve that continuously delivers good sound...

In general, as you increase from 12 o’clock you may be boosting both lows and highs along a predetermined Curve, when you turn counterclockwise from 12 o’clock you are cutting frequencies at predetermined locations... based on much study of the source sounds.

The TONE in each section is worked out for the sounds in that section. It is not just a simple control - there is technology behind it. Not sure if it will “fix” your “struck at its fullest” issue (I’ve yet to hit a piano that hard), you would do best to judge that for yourself. Any way, each sound has a storeable setting for the “Tone” Control.

The actual TONE setting you determine is right for your selected instrument will be stored with that sound in your Live Set.
The MASTER EQ is global... all sounds go through the Master EQ... the Master EQ is not stored but is always “live”.

Many thanks for taking the time to answer in detail.
I'll need to go back when I can and experiment with the tone setting.

Obviously you have answered the question as asked - ie no the editing functions are not available.
That feels like a huge call on Yamaha's part - it does make me hesitiate to press the button on a purchase just at the moment - maybe the tone adjustment is the key.
And I do absolutely inderstand what the idea is - ie to make things just right so you don't need to do heavy editing.
And - this issue aside - for me these new boards are perfect.