There is a great site where you can test out technical analysis by comparing it to randomness -nonrandomwalk. You have to love the name. At the site, you practice trading blindly (you don't know what stock you are trading or what year you are trading it) on historical data and then compare how you did to a set of traders randomly trading the same stock. The results are often humbling.
With regard to Malkiel, his experiment has a fundamental problem. Just because coin-flipping can produce classical patterns, that doesn't mean that the patterns in the market are random. One would have to look at the frequency with which patterns appear in coin flipping versus actual data. To my knowledge he did not do that. People who have (Andrew Lo) have found that chart patterns occur with demonstrably more frequency than would be expected if markets were just coin-flipping.
Consider another example from a standard probability class. Imagine a thousand apes randomly typing on a thousand type-writers for an infinite amount of time. What is the probability that they will eventually, in combination, type the complete works of Shakespere? The probability is one. It is an interesting mathematical proof. Does this mean that the works of Shakespere were random?