Does album gain circumvent the intentions of the album's producer? If one track was recorded with the intention of 'standing out' from the others couldn't album gain potentially alter that?
I think the point of it is that it does exactly the opposite.
If you use normal Replay Gain, all the tracks on an album are considered individually and therefore all end up at more or less the same volume. This really leads to problems with, say, Pink Floyd albums where short tracks of dialogue/sound effects end up disproportionately loud, and when tracks run into each other there can be a big difference between the volumes.
With Album Gain, the tracks retain the same relative volume to each other that they had originally. So overall, albums are roughly the same volume compared to each other, but within each album there can still be quiet and loud tracks.