I'm very interested in both of those. Would you care to explain? If not, do you have any particularly good resources (besides a google search, which I can do myself)?
So, how does that work, exactly? Does macrolet tell lisp that since the macro is only defined in that scope, it should search more carefully for it, because it doesn't have to worry about slowing down the whole program?
Err, no. It simply means that the particular symbol for it is bound only within the scope of the 'macrolet form. In practice, most of the time, the desire for first-class macros is really just the desire to bind a particular symbol to a macro within just a particular scope, and 'macrolet does that.
For other cases where a macro expansion should be used more often than just a particular scope, then usually the module or whatever is placed within a package and a package-level macro is used.