You remarked,
"I just realize that with the argument about an emulator not being "synchronized" (which is false) that very argument exclude the romulators. Whith a Romulan (pun intended) you do NOT have an exact replica of your system (which will be EPROM). Even worse, with internal flash/PROM devices, you replace an internal program code device with an external program code device and that is so far off in timing that even calling it a simulation may be too much. "

Actually, the manufacturers take great pains to ensure that emulators do stay in synchronization with the target system.
The synchronization to which I referred is synchronization of the code running in the target MCU to the processes it monitors and controls, outside the MCU but in the target system.
Actually, "rom emulators" are of no use at all in a system wherein there's no ROM. A rom emulator has a cable to a pod that connects the target system ROM socket to the SRAM in the emulation hardware, an arrangement which is not difficult to build yourself, BTW. If the target doesn't use the external ROM, the ROM emulator is of little use.

There was, at one time, BTW, a product known as ROMULAN, which was an ethernet-interfaced ROM Emulator.

RE