I honestly think many of these Alt coins are pump n dump schemes. You can make some good profits on Alt coins, if you time your exit before they collapse. The most stable and reliable Crypto currency, since 2009 is Bitcoin and that is not even disputable.
So my strategy is to play with Alt coins and to move my profits to Bitcoin in the end. Bitcoin is my store of value, like Gold is for many other investors.

We have personal strategy applied for every situation in the market, some may have same strategy like you just posted, and have different exit plan. Market is Volatile, anything can happen at any given time, the price value of Bitcoin may goes up and goes down, Yes, i am more inclined to Bitcoin as my main coin in investment. Traders often time use the same strategy for short term transaction on the market.