If you're talking about training sessions with a gear 2-3 higher than your normal cadence, then yes, I think there can be a strength benefit there. And I have some anecdotal experience that would support that (though far from conclusive, as the gains that I experienced were during a period when my overall fitness was still on an upward curve).

However, I would urge extreme caution in this area. When you say things like "ridiculously high gear" and "max gear", I think you are not only on a dangerous path, but on a path to certain injury. The only thing that really scares me (other than an accident) is an injury that will prevent me from cycling... most especially anything related to the knees. And as eric mentions, the tendons and ligaments are especially vulnerable, especially if you do not already have years of base miles built up. Mashing just is not worth it, in my opinion. The strength will come, there's no need to risk injury trying to hasten the process.