An interesting conundrum

Recent research has shown that a common anti-epilepsy drug can restore brain plasticity and allow adults to develop perfect pitch (everyone be on the watch for pop stars making a run for Mexican pharmacies), and that there may be potential applications beyond music, such as languages.  There is a catch though:

If we've shaped our identities through development, through a critical period, and have matched our brain to the environment in which we were raised, acquiring language, culture, identity, then if we were to erase that by reopening the critical period, we run quite a risk as well.

So imagine you're company needs to send you to China to oversee a new manufacturing line, while you are there you take this drug to help master the language and you return to the States a full fledged member of the poliburo.  Not a pleasant thought is it.  So where do you set the breakpoints on the cost-benefit analysis? Hard to say isn't it?  On the other hand I have heard some theories that Alzheimer's may be caused in part by a loss of brain plasticity so it seems that this may be a potential treatment at the risk of actually losing the personality of the person that you are trying to treat.  Is that an acceptable outcome?