Lawrence Olum played well for the Portland Timbers, and the MN Thunder D2 teams. He also played well for the Austin Aztex D2 team before it became a D3 team and he had no choice but to move down to the USL "Pro" D3 Orlando City team. The year after it became Orlando City
he left ASAP after the season ended... Great example Bernie
http://en.wikipedia.org/wiki/Lawrence_OlumI would call that leaving as soon as his D2 contract which became a D3 contract ended.
Following an unsuccessful trial with Los Angeles Galaxy, Álvarez was signed to a professional contract by the USL First Division expansion franchise Austin Aztex after attending the Aztex open tryouts in California in March 2009. He made his debut for the team on April 18, 2009, in Austin's USL1 season opener against Minnesota Thunder.
http://en.wikipedia.org/wiki/Yordany_Álvarez
On January 21, 2010 renewed his contract by signing a three-year deal with the club.[4] Prior to the 2011 season, new owners purchased the club and moved it to Orlando, Florida, re-naming it Orlando City S.C.. The club will play in the USL Pro league in 2011. At the end of the 2011 USL Pro season, Álvarez signed with Major League Soccer club Real Salt Lake on a loan agreement.. Sounds kinda like he did not want to stay in D3, ahe Bernie??
There are many more NASL players Bernie
-Four from Montreal NASL's team moved up...
-NCS MN Stars had Scott Lorenz and Jack Stewart move up...
I could go on but I think you made my point better than I did:
As soon as the talented players can leave the USL Pro league, they do move up and away.