(sorry to those of you who read in the threaded mode.. this is out of order..)
one poster comments:
There's nothing wrong with the mainstream, of course. But it only flows in one direction.

yes, well maybe.. i guess.. but..

i live in NYC. We have a river, The Hudson
(well, technical it is a fjord, and technically in NYC (but not in NYS its called the North river, but these quibbles aside)

it is a large river. (well over 1 mile wide in NYC area)

It is a long and deep river (NYC/harbor does silt up, but just a few miles north of the city, where there is less silting, the river bed is over 250 feet deep)

the river has a 'backflow'--that is the ocean and tides flow upstream-- over 50 miles. (at high tide, the backflow current is much stronger than the downstream current, and the river flows 'upstream'!)

Most east coast rivers have water falls and the falls stop tidal backflows, (and since the falls are often less than 50 miles from the mouth of the rivers.. the back flow is limited) --the first falls on the Bronx river is less than 10 miles from mouth of the river, for example.

but tidal backflow is not unique to the Hudson.

and backflow is not only caused by tides.
several tributaries to the mississippi river creat backflow.

The mainstream, even when you talk about rivers, is differentiated because there are frequently (if not always) contrary flows.

I would argue the term mainstream evolved to clarify the predominant flow of water, but that there are backflows and contrary currents in almost every river (and eddies, form and collapse to deal with the backflows.)

--the same situation exist 'socially' --A mainstream idea (or behavior) might be the more common one, but there are always contrary ideas and behaviors going on.

Rereading, and trying to clarify, i recognize is the BUT in the second sentence that is bothering me.
There's nothing wrong with the mainstream, of course. But it only flows in one direction.(EA)

the but negates the whole first sentence. it implies there is something wrong. and then goes onto tell you what is wrong, (it only flows in one direction)

its like saying I agree with you totally, BUT for one point--well if you don't agree on 1 point, you don't agree totally.

So it seem the mainstream (ie, the predominant flow ) has 'nothing wrong' --Except it flows in one (predominant) direction (that is, it is the main stream.)

mmm.... i agree total with the person who posted the comment, BUT--