I also believe that this is a nice strategy. We may see another drop or two. We're not safe yet. Maybe even a new long-time low. But that strategy is a very good one if you believe in Bitcoin's long-term success! (I do, as well)
if you really believe in the long term future of bitcoin then you can just sit and relax. but that's not the case for a lot people. they say i'm in for the long term, but as soon as the price drops they quickly sell. called weak hands.
if you really believe in the long term of bitcoin, you should buy more, not just hold and sit there, thus i seconded the choice of the OP, a good strategy indeed, but in my case i would do only 5, well it depend on how many money you can afford to lose