I've been poking around on the internet and found some discussion of a strength coach named Jay Schroeder and some of the training techniques he uses. He gained some noteriety for training Adam Archuleta, a football player, who blew everyone away by his performance in the NFL combine. Since then he's trained several professional athletes. Some of Schroeder's techniques are pretty far out there but he uses one that is similar to the statics used by Coach Sommer. The major difference is that he has the athlete hold the position for 5 minutes. There is a forum located at http://wgfforum.llsint.com/Forums/index.php and several people there report having experimented with these longer duration isometrics with good results.
Here's a link to a site that has an interview of Schroeder. http://mostshockingsportstraining.com/ Some of the claims are pretty far out there.
I'd be interested in hearing opinions on this training. The gymnastic training as discussed here seems primarily geared toward upper body movements. If Schroeder's ideas have any merit they might be good to use for lower body.