In the article (which is for subscribers) or the podcast (which anyone can listen to), Silva describes the process for making the guard and you find out that it's a relatively mundane process. Also, the elbow guard's main function is, not surprisingly, to protect Barry Bonds's elbow. Silva wants to make a guard that is as light as possible so the person using it doesn't feel it at all and think it's a hindrance.
Silva also mentions that he hasn't had to change the mold for the guard in the last 12 years because there has been no meaureable change in the size of Bonds arm in that time and players like Mo Vaughn and Rickey Henderson have worn similar guards and have had similar sized arms.
Update - From Edman8585, you can read another rebuttal of Witte's report.
My question is: Why would Editor & Publisher run such a piece? It's not exactly what their readership is looking for.