Does the NG have a form of early incarnation of MCAS too? I can't provide certified FCOM documentation to CYA, but I can confirm below is a verbatim copy, found on the web:
B737 NG Flight controls, slide 37
It is not really clear to me exactly what is involved in making the stick feel heavy at high AOA from the description, the EFS, STS trim or a combination of both.
Here is the description in question:
"As airspeed decreases towards stall speed, the speed trim system trims the
stabilizer nose down and enables trim above stickshaker AOA. With this trim
schedule the pilot must pull more aft column to stall the airplane. With the column
aft, the amount of column force increase as the EFS module increases pressure to the
elevator feel and centering unit."
