average of dBs or dB of average?
If I saw the expression "The average gain of the path is 10 dB", I would assume that the gain varies around 10 dB - if I take a number of measurements at different times, I might see 10 dB, 12 dB, 8 dB, 9 dB, 11 dB...., with the average of those measurements being 10 dB.  

I don't know what a "dB of averages" would mean.