Do open supply licences cowl the Ship of Theseus? – Terence Eden’s Weblog

I recently downloaded a single-page HTML template for a project I was working on. I wanted a good-looking scaffold to help me getting running quickly. The code had an attribution licence which I was happy to comply with.
I ended up removing about a whole bunch of the HTML that I didn’t need. That also allowed me to remove the majority of the CSS which was unused. I deleted all the JavaScript. I added some semantic markup and updated a few of the outdated coding conventions. Newer CSS was also added to support modern features. And I replaced all the default images and fonts with something I preferred.
In total, 75% of the HTML was rewritten and 61% of the CSS had changed.
Is there enough of the original files left to warrant attribution according to the licence terms?
Let’s take it to an extreme. Suppose I really loved the background colour used by a piece of free software. If all I copied wasbody { background: #6082B6; }
would that require attribution?
I feel there is a affordable argument that de minimis non curat lex – the regulation cares not for small issues. Is anybody critically going to argue that I stole half a dozen bytes? Might they show that I copied that single line from them? Would anybody care?
And but, morally, I really feel that I ought to give credit score.
Very like the apocryphal sculptor, I have removed everything that wasn’t necessary. However I feel the poor sod who lugged the block of marble deserves acknowledgment.
At what level do you say “this has modified a lot that it’s not essential to abide by the unique licence”?