Using the SD library with the ESP8266 DevKit
After some trial and error got both the screen and sd card reader working sharing the MISO and SCK lines.
I was using a display wit the Adafruit ST7735 driver (and their library), worked fine with both hardware and software, but the SD card reader (generic, not even a part number on it) was able to work only with hardware SPI as the standard SD library does not support software SPI for some reason. 
The most important takeaway is this: The SD library internally uses the predefined MOSI,MISO and SCK pins, but fot the ESP8266 dev kit they were mapped to pins labeled HMOSI, HMISO and HSCLK - D7, D6 and D5. Now that I think about it, the H must stand for "Hardware", if only I had this epiphany sooner.