I often use Invisibility potions if I just want to run past groups of enemies. The basic duration for a crafted potion is 17.6 secs and I have 2 rings and a necklace with the alchemical amplification enchantment adding 3.6 secs each. Since the patch, the enchantments are not applied anymore though I can take off the necklace and the rings and put them back on at which point the duration is shown correctly and also applied the right way but shortly after it reverts to the basic potion effects duration without the enchantments applied.