Posted 2008-May-08, 18:09
I don't think there is a such thing as "standard 2/1" per se. However, most detailed treatments of 2/1 bidding do seem to include walsh responses to 1♣. In particular, BBO Advanced includes walsh.
If I were to agree "2/1" with a good player without further discussion, I would assume walsh responses to 1♣ (i.e. bypass diamonds in order to bid a major unless holding GF values, after 1♣-1♦ opener bypasses major(s) to bid 1NT with any balanced shape).
Walsh responses to 1♣ are definitely not part of SAYC, which is up the line bidding. This is more clear cut, because SAYC is a specific system (admittedly not all sequences are specified, but there is a set of rules that does answer this specific question). On the other hand, "2/1" is a style, a general group of systems which includes methods such as BBO Advanced and the Hardy and Lawrence 2/1 styles, as well as other methods.
Adam W. Meyerson
a.k.a. Appeal Without Merit