mgoetze, on 2015-July-15, 18:05, said:
Also if finding 5-3 fits is the priority then you can play the style of T-Walsh where completing the transfer shows 3. (I prefer my style to that one, so...)
Most methods work in an uncontested auction, but they are in a better position that the rest of us when the auction goes 1♣-(Pass)-1M-(Pre-empt).
Another advantage is knowing about a 5-4 fit. One of the nice things about playing Kaplan Inversion is when the auction starts 1♥-Pass-1NT showing 5+ spades, Opener can raise aggressively holding 4-card support, getting to the 3-level has some security when there is a known 9-card fit. Contrast that with the natural auction 1♥-Pass-1♠natural-Pass. Now it's more dangerous for Opener to go to the 3-level when Responder's trump suit could be 10xxx (or worse); meanwhile Responder is reluctant to make a marginal game try after 1♥-1♠-2♠ in case Opener transpires to only have 3-card support.
ARF/DG have similar inferences available after 1♣-P-1M-P.
I assume that ARF/DG like these inferences over 1♣ and 1♥ openings, judging from their extension to play something similar over 1♦ openings. As I recall, version 1 used 1♠ as 5+♠, 1NT as 5+♥; then after a while they switched the meanings of 1♠ and 1NT. [This gave us something to think about - what should 4th hand's doubles mean?]