In a first course in Information Theory, when the operational interpretation of channel capacity is introduced, it is said to be the highest data rate (in bits/channel-use) of reliable communication. While reading a few papers, I came across channel capacity being expressed in units of bits/s/Hz. So I was thinking about the connection between the two units and came up with the following explanation. Please let me know if this is wrong.
For a bandlimited channel (bandwidth = $W$ Hz), you can transmit at $2W$ symbols/sec by the Nyquist sampling theorem. So the rate "per bandwidth" (spectral efficiency) can be written as 2 symbols/sec/Hz. If each symbol is 1 bit, then you are transmitting 1 bit in each of the samples. So is 1 bit/channel-use equivalent to 2 bits/sec/Hz?
What is one "channel-use"?