[sgtnoodle]

You can do it in linux, with drivers that implement packet injection. You're giving up a lot, though. I think you're right about it being a wash with regard to control overhead. In particular, because of the data ACKs, the firmware can aggressively ramp the 802.11 frame data rate up and down. Thanks to packet aggregation, the cost of the frame preamble gets amortized across all buffered up data. Letting each application schedule its own transmission would quickly eat up the available channel bandwidth in frame overhead. It works for a single specialized application, but monopolizes the entire shared channel.

Folk do that sort of thing when transmitting low latency first-person-video from drones, using commodity wifi hardware.

[jesprenj]

CNLohr at Youtube did this to use ESP8266 at absurdly low power usage, only waking up every couple of minutes to transmit a 802.11 frame without connection handshake. https://youtu.be/I3lJWcRSlUA