In /interface wireless manual-tx-power-table, there are an extra set of parameters that are not described in any of the manuals. They are named HT20-1 through 8 and HT40-1 through 8. What are these, please?
They are related to 802.11n (draft) 20MHz and 40MHz RF bandwidth modes.
Mikrotik probably haven’t documented those parameters in the manual, as 802.11n is not even supported yet.