During one of the tests I had set the RTS threshold to 1084 bytes. The packet received by the sniffer was 1088 bytes including the MAC header, data payload and the CRC. But still RTS/CTS transactions were not seen. When I increased the packet size by another two bytes RTS/CTS transactions were observed.
The IEEE standard also doesn't mention this explicitly. Could you please clarify? The same query is also valid for the Fragmentation threshold.
In addition, that standard says that "the length of the MPDU shall never be larger than the aFragmentationThreshold unless WEP is invoked [in which case} the MPDU shall be expanded by the IV [initialization vector] and ICV [integrity check value]... this may result in a fragment larger than the aFragmentationThreshold."
This was first published in February 2004