If one were to run a pH check on their solutions they would find the pH is extremely high on the alkaline side *immediately* after the product is manufactured. Over stabilising time frame that pH level drops to around base 7 odd. I believe this is why EIS/CS is so effective at times. Two differing products dependant on time lapse from when the product is made to when the product is administered.
I ran a pH test on two batches of mine, one batch tested within hours of being produced and the other a fortnight old, the above was the result. It's an aspect of EIS/CS I don't think most are familiar with or aware of regarding possible efficacy in some circumstances, and pH level *may* play an important part here, who knows?
Just my hypothesis, but I'm sticking to it until a more 'in depth' explanation or analysis can be put forward, and I can't see that happening any time soon.