What do you mean "why"? Are you so incompetent that you can't understand that people use more than one browser and multiple operating systems? This is default software, it must work for everyone, not just selected few.
This isn't 1999 when designers only worried about making their website work in one browser. These days users use many operating systems: Windows, OSX, iOS, Android, all of them deal with fonts differently and when proposing a solution that deals with fonts you must make sure it works for all of them.
Yet you seem to live in last century, insisting on solutions that work only in selected 1-2 browsers. Do you even know anything about design? Doesn't seem so. Your own website looks like it was designed 10-15 years ago, still using tables for layout, images designed in MS Paint and fonts that seem to be selected randomly. You have released exactly 0 styles, you have no experience whatsoever working with mobile designs.
If you want to constructively prove that your solution works, please provide proof instead of posting more gibberish. Why are you refusing to do so? In last topic I've provided proof that your solution is crap (just like almost everything you say) and in response you tried to derail thread into completely different issues, just like you are trying now.
P.S. -moz-linear-gradient is NOT valid CSS3 unless you are stuck with ancient Firefox 3.6
DionDesigns wrote:phpBB has shown no interest in platform-consistent fonts. The current product has platform-consistent font issues that are orders of magnitude worse than the miniscule issues of a few buttons. The product in development has platform-consistent font issues that are orders of magnitude worse than the miniscule issues of a few buttons.
Those are completely different issues. Just because some other part of style has problems, doesn't mean you can add more invalid code. Please stop trying to derail topics into unrelated issues (again).