I consider myself an audiophile and yes, I do modify my equipment every now and then.  I can hear different improvements bought about by different modifications, absolutely. Am I crazy, absolutely not.  Do I believe in "things that does not exist"? No. I make my money one day at a time and will never throw it away lightly. 
Many of my friends are also into modifying their soundcards, CD players and cables.  Are they all crazy? I don't think so.  There are millions of audiophiles out there doing what I do  (that is why there is a DIY corner in this forum) Are they all crazy? I don't think so. 
Have you tried any of those mods in that blog and other DIY forums? I don't think you have... 

 So, please don't discredit something that you have not tried... Your personal perception is no substitute for proof either. 
Peace.