To be fair this was Excell 25 years ago, may no longer be true.

One of the other bugs (the Quark/ATM one) was also because of the programmers were worried about writing over stuff that hadn't been completely erased, the Quark guys wrote a string with 2 spaces at the end through a box that masked the end of the string, the ATM font renderer saw it couldn't fit the text so it split it in half and tried again so it drew N/2 N/4 N/8 ... strings. It spent all it's time in the 68k's multiply instructions figuring out how wide the strings (and substrings) were, our fancy 24-bit character rendering hardware was an afterthought

In all of the software you’ve written, are you aware of how many on-screen pixels you’ve overdrawn?

> To be fair excel would erase places white that it wanted to write up to 9 times before it drew any black pixels

I feel like I'm having a stroke trying to read this, what does it mean??