Not only am I tequila newbie, I am new to mixing cocktails. All my life, mixing a drink meant putting some ice and water in my Scotch.
Recently, reading about mixing drinks, several times I have seen the instruction to "shake and strain into glass on fresh ice" or something similar. With my Margaritas, I have been shaking the tequila, fresh lime juice, agave nectar, and ice and then dumping ice and all into the glass.
Why would I want to strain just the licquid onto fresh ice?