Think of all your code as a single file with line separators, file separators and a special UI that considers both to present these in a text editor. The exist

Think of all your code as a single file with line separators, file separators and a special UI that considers both to present these in a text editor. The existence of large files is mostly just a style issue. Text editors with different or lets say more semantic interfaces to the code would not care about file size. You could then happily have 1M loc in a single file. You would care about it as much as you care about how the code was laid out on sectors and pages on your HDD.