The DNA of Louie’s Grill seems pretty basic: Simple, good food. A great location on Madison Street. And Louie.

Now, happily, Louie and Ellen Politis, owners of the grill for the past decade, are planning a major expansion, taking over the space next door and doubling their space. That’s great news. Even better is that Louie and Ellen understand the simple magic they’ve created and don’t have some high-faluting desire to reimagine the grill as something more or different than what it is today.

Sure, more tables so customers aren’t rushed out during rush hours. They plan to add a bit of a 1950s diner theme. That’s OK if they don’t turn it into a Disney theme park. A place for the ever growing, customer generated collection of lighthouses. Absolutely.

But they understand they can’t mess with the open kitchen that allows customers to see Louie at work. They shouldn’t mess with the waitresses who can dish on all levels. The menu is fine. OK, add waffles but don’t go all Sunday brunch on us.

Louie’s is about perfect right now. Growing it some is fine. But don’t mess with the DNA.