We have seen from the Kelly formula that even for investments you have higher odds of winning (for example, 60%), if your net winning rate and net losing rate are the same, then at most you should commit a very small % (a small single digit percentage) of your available funds to this transaction. Unless your available funds amount is a big number, otherwise due to higher transaction costs, it's simply not worthwhile to invest that very small % of funds.
So the key is to raise the Reward : Risk ratio for each transaction to make your investment transaction meaningful (my rule of thumb is at least >3), of course this implies that before each actual investment transaction, it's extremely important for an investor to evaluate the Reward : Risk ratio and only commit to the transactions with high such ratios.
How to set appropriate reward and risk levels for each investment transaction is a topic for future series of blog discussions.