Don - the say this in the article:
A possible explanation for the conflicting geodetic and geologic data is that the region of shortening represents the contractile side of a slowly east-propagating deformation pulse generated by the 1915 Pleasant Valley and 1954 Dixie Valley and Fairview Peak earthquakes

The entire basin and range is in an extension process - in some areas it is compressing versus extending - this phenomena is what I believe they are calling a 'pulse' - the pulse is associated with the quakes mentioned - how long did it last? probably as long as the earthquake and still today as it is still compressing - How did they measure it? With geodetic data and GPS.

They are trying to see how transient effects from an earthquake on one fault may influence patterns of stress and seismic strain release on others - the mystery seems to be that there is compression occuring in an area of extension and the use of modern tools like GPS are helping get the information much better and faster than older mehods.

Or at least that's what I got out of it.

Canie