matching cartridge and speakers

A lot of talk about matching cartridge and arm, and cartridge and phono. And rightly so.
However, that's not all, I believe. These are two points where energy transformation happens. The rest, with the exception of turntable itself, are just supporting structures and "wire with gain". Cartridge and speakers make music.
Well, outside of the room acoustics, the speakers and cartridge are the two types of components that deviate the most from linear response. It's because they are electro-mechanical instead of purely electrical devices.

That acknowledged, how would you match them? Would you get printouts of the frequency response curves from all the main contenders and see where they compliment or don't compliment one another? Then just add the room acoustics to that equation and you'll likely have quite a saucy stew.

Cheers :)
Interesting question, because you are right, all is a "chain". The X-over from the connected speaker can be a 'black hole' or can serve you more information. When that one is done right it is possible to hear more information, even when the overall gain from your source components is lower...
There aren't any other two components in the audio chain which are more independent from each other than the cartridge and the speaker.
They both are interfaces to the purely electrical part of the audio chain.
Their jobs are entirely in reverse to each other and to choose a cartridge because of a certain speaker or vice verse means nothing than masking apparent faults in either.
There are huge interactions between the output stage of an amplifier and the x-over of a speaker.
This is an electrical interaction (resistance, inductance). Very important to match here.
The cartridge/tonearm is a spring-mass system - a mechanic-dynamic interaction between the two components.
Again - very important to match.
But I see no objective reason to match a cartridge to a given speaker - other than to mask sonic faults and so to fit into a personal sonic matrix.