I think that the scenario that you are describing, bitserve, is a perception problem and even perhaps a problem of someone who should have taken more out of their bitcoin investment while the prices were on their way up, rather than experiencing a kind of panic feeling of overinvested when the prices are coming back down - even though you are correct to presume that perhaps any of us could fall into one of these kinds of perceptions of mistake where we see the value of our BTC holdings falling rapidly and therefore, conclude that our best strategy would be (for our own psychology, planning and regrouping) to dump a bit of the bitcoin in order to feel better and to lock in some of our gains before the value goes a lot lower.

Some diversification can be a good thing - however, sometimes we have to be careful about what we are diversifying into.. sometimes people try to sell you crap, with the concept of "diversification," and also I believe like Hairy mentioned, the need for diversifying might be less if you are feeling "overinvested" due to price appreciation of the asset, rather than due to having had put that much into the asset- and sometimes there is a considerable justification to maintain some overinvestment into an asset that is performing well rather than putting money into poorly performing assets merely for the sake of "diversification"... so one way to "get rich" might be to allow some of your profits ride for a long time within a strongly performing asset, such as bitcoin... because there is really no fundamental reason (including at this time) to expect that bitcoin's future performance is peaked out or anything like that.  Not yet anyhow.