Perplexing---> I think that in the main line white wins his pawn back with ease, usually he gets a large centre in return for passed a+b pawns, the main line is as follows:
e4-e5 for White usually never comes as Black plays e5 himself in most games.
The main line as shown by FM_Holland is the Abrahams-Noteboom variations, and is quite complex...
Perplexing---> I think that in the main line white wins his pawn back with ease, usually he gets a large centre in return for passed a+b pawns, the main line is as follows:
e4-e5 for White usually never comes as Black plays e5 himself in most games.