Question about dynamic rate control

http://libretro.com/forums/showthread.php?t=3505&page=4&p=25993&viewfull=1#post25993

In that post Twinaphex says regarding vsync issues, setting the delta to 0.00 is preferred to get smooth video, but he also says “I guess you might be on old configs where it’s still set to 0.05” I don’t understand this because retroarch still writes 0.05 as default.

Isn’t it always preferred to use 0.05 for everything?