Right, exactly. Next means after the present or immediate one. Next Wednesday would be the first Wednesday after this Wednesday.
Exactly. If it is Thursday the coming Wednesday is not immediate and therefore I would never refer to it as this Wednesday.
I would say "this coming Wednesday is R"H" or "next Wednesday is R"H" but
not "this Wednesday is R"H".
If you need a Mashal try this one.
If you are waiting for the train and ask "when is the next train?" you mean the first train.
If there is a train in the station and you ask "when is the next train?" you mean the second one.
The difference is whether or not there is a "this" train.
Same thing here. If, and only if, there is a (proper use of) this Wednesday does next Wednesday mean the second Wednesday (on Mon. 9/12 this Wed. means 9/14 and next Wed. means 9/21).
If you use this explanation it would answer all of the questions you (of the minority opinion) have brought up.