If you had actually had meters everywhere that would be true, but there usually isn't metering available on every unit. Take pre-amps for example. I have meters on the V3 but none on the MMA6000 or my Church Audio pres. If I run the V3 in front of the R-09 I can check levels on both of those units. Because the R-09 doesn't accept a very hot signal, the V3's meters only light up the first few lights when I set the r-09 input at 10 (the lower end of my comfort range). That's OK, nothing is overloading, but I don't really need the meters on the V3 in that case. It's sort of the opposite of the brickwalling, the V3 has way more headroom than needed in this case and is in no danger whatsoever of clipping. But the V3 is a more professional piece of gear designed for higher levels and with more headroom in its analog sections.
I've thought about doing the math to figure out at what point I will be close to clipping those other preamps so that I actually know what's going on with the gain staging in my chain. I know the sensitivity of the mics and have specs on some of the preamps, but the math part is a bit beyond my skills and I can comfortably run my gear without knowing exactly so doing that would be a bit academic. That's something I'd need DSatz or one of the EE's on this board to help me through.
In actuality, all-in-one recorders should be less likely to have problems because the manufacturer is responsible for making sure all the components work together at appropriate levels. Yet cost constraints manufacturing inexpensive recorders means that there is no budget for extra headroom for unusual 'just in case' scenarios and these types of problems can manifest with extreme settings.