Why would that be true? I have a friend named Don Demsak (known in the mid-Atlantic as "DonXML")...he's one of the most widely-sought speakers on the East coast. He has a saying...."You are probably doing your career harm if you are not learning a new major tool or major functionality every 9-12 months" (or words very close). I strongly agree with him. The more you learn, the more you CAN learn. The process of learning helps you the next time around (assuming the person is intelligent enough to have developed some basic methodologies for integrating new information)
Take two developers of roughly comparable intelligence, age, experience, etc. One has been working in Fox for years....the other has been working in Fox, then moved through maybe 2-3 major cycles of .NET and SQL Server. Both are asked to learn tool XYZ....who do you think is more likely to get up to speed quicker?
