One thing that makes me think the westward adjustments should not continue is based on persistence forecasting. Granted, this is not a good way to make accurate forecasts, but can be generally useful. For example, back in 1996 ( I am sure Phil remembers this) any shortwave that moved towards the east coast generated a snow storm, even innocuous looking weaklings. It wanted to snow, and it wanted to snow over my house, and it did to the tune of 66" for the year.
Since last year, the NE GOM has a bullseye on it. Even without tropical systems, rainfall anomalies are in a well-defined pattern. It is illustrated by the drought monitor map at the link below:
http://www.cpc.ncep.noaa.gov/
Recent climatology suggests the biggest impact will be east of the Mississippi. Eventually, this analog will no longer work, but I go with them until they do not. You can pretty much see by that map the mean position of the offshore high. That doesn't mean I think NO is out of the woods, just that I don't expect forecasts to keep shifting west.