Inherited code checking Struts method name
I don't believe there's any good use-case for this code.  I know it makes for a boring answer, but sometimes the correct thing really is simple and boring.  As you say, the Struts framework should always redirect to the appropriate method and fail entirely otherwise.

Even the scant lines you posted have some bad/useless programming practices, so my guess is that the developer thought he was being thorough and clever by tacking on needless framework.

if (method != null &amp;&amp; "myMethod".equals(method)) {
    // Perform the actual work


He already checks for method != null and then checks for "myMethod".equals(method).  The only reason to use the second construction for a String comparison is to avoid a NullPointerException... which he's already done by checking against null.  So either he doesn't know that Java short-circuits conditions, or he has no idea what the purpose is behind the second construction.

Also, it's generally a bad idea to have huge wrappers around entire method bodies.  It would be a better design to have something like this (if it were needed at all):

if(method == null || !method.equals("myMethod") {
    return;
}

//do stuff


... Or you could write the conditional as if(!"myMethod".equals(method)), but I honestly really hate the flipped comparison rather than explicitly checking for null.  I suppose it's a matter of taste, though.

Anyway, bottom line: no, there's no use for it, and there's evidence that the original programmer didn't entirely know what he was doing, anyway.