As far as I can tell, Mikrotik does not get it. A moving terminal, lets call it a mobile, and multiple fixed stations must use what we radio people call "diversity". Diversity could be as simple as switching fixed stations in accord as to which one has the strongest signal. I believe the mobile could work with multiple terminals all at the same time if they all had the same MAC, and were synchronized. By synchronized, I mean the radio transmissions intended for the mobile from all fixed stations would be close to the same instant and on the same exact frequency. The more simple technique should work on the existing non synchronous capable hardware. Simple. Switch the transmitted packets off except for the fixed station receiving the strongest signal from the mobile. send packets from the mobile to a central switching unit only if they came from the fixed station receiving the strongest signal. I bet that is possible with existing hardware and only minor modifications of Mikrotik OS. There would need to be a central station controller that would manage it. That requires some additional software.
I think you can set up access points to use the same SSID and all have the same wireless MAC. That would mean the mobile could not tell what fixed station it was talking with, and will treat all that are receivable as interference. Likewise, all the fixed stations will think the mobile is registered and send the same mobile packet on to the LAN. Right?
Maybe it could be done with existing Mikrotik OS, and as I am not expert in it, I do not know what commands can be loaded. That it seems not to have been done tells me it is difficult if it is at all possible. Anyway, think first about packet switching diversity. If you like, look up diversity radio reception on your favourite search engine. -ok... back to sleep.