I suggest they CAN. But what to measure?
Not what I found. It is the spread of the upper harmonics. DP distortion decreases with frequency as it is basically just a LP filter. Miller is more even, so above 20K, it will have more harmonics getting through that can excite the breakup. This causes IM that we hear down in the critical range. This is one of the reasons I advocate the tweeter crossover be a band pass. Roll it off steeper above 17 or 18 so those harmonics never reach it. The advantage of Miller, or two pole, is a lower level all the way through the normal pass band. So if you can avoid the top end problem, you gain across the board.
Appropriate modifications for speed and stability need to be made. Cost me two sets of MOSFETS to get it right. The critical speed here is that they blow up faster than you can spring to the power switch.
I did not invent this, I was prodded along the path of confirmation because a preeminent amplifier designer was upset my wife hated his pride and joys preferring Rotel. The question was why? After I understood it, I went on and built better speakers with less sensitivity to the problem and then, the "better" amp was in fact picked by my wife as much better. I still run my modified ( extensive) amp and it is clean enough we can hear the differences in DACs.
My assumption, The designer of the Rotel ( Dave I believe) and the other entry amp ( Erno) expected them to be used on more affordable speakers. So they chose the topology appropriately. John expected his amps to be used on serious upscale speakers, so chose alternatively. Smart folks all around. I just followed along soldering iron in hand to learn what they knew. There is no difference is production cost, so it is an engineering decision, not market pressure. It is possible, and I have modeled it in Spice, that more complex IPS and VAS will have lower inherent distortion than DP compensation on a better amplifier can beat Miller on the simple one. I do not use a Darlington differential VAS. More can me done to my CM and CCS. There seems to be magical sweet spots for the ratio of IPS gain and feedback you can adjust by the LTP degen resistors. Cordell and Self did not discuss this.
A perfect amp with a superior source, or some point where it becomes irreverent, would not have this limitation. I know amps like the Benchmark, PS5 ,and C298 are so clean, the subjectivists have nothing to say, and the objective measures say they are fantastic. They are at probably 100 times less distortion than my amp or the prestige amp I had. Good enough? I wish I had the cash to find out. What I do have is enough to do another speaker build as (some) tweeters have gotten better. Can I build a speaker that is good enough that DACs sound the same? Don't know. But now I have a system with no glaring deficiencies in the electronics, I can concentrate on my speakers. I have hauled them around a couple of times and they hold up pretty well to the 3 to 5K competition. A tiny less detail you think is the lower mids, but I suspect more of a miss in phase across the crossover. Correct at crossover, but divergence is too fast. My guess. I think I can do better.
Distortion is additive. It's not the weakest link, it is the sum total of the chain.