Seems the people behind grbl will disagree...
" Streaming Protocol: Simple Send-Response [Recommended for Grbl v0.9+]
The send-response streaming protocol is the most fool-proof and simplest method to stream a G-code program to Grbl. The host PC interface simply sends a line of G-code to Grbl and waits for an ok or error: response before sending the next line of G-code. So, no matter if Grbl needs to wait for room in the look-ahead planner buffer to finish parsing and executing the last line of G-code or if the the host computer is busy doing something, this guarantees both to the host PC and Grbl, the programmed G-code has been sent and received properly. An example of this protocol is published in our simple_stream.py script in our repository."