Quote Originally Posted by Michael R 1974 View Post
PE - can you elaborate on this? Are we talking about uniformity or other issues? Some people swear by prewetting, others say it doesn't improve anything. No evidence is ever presented either way. What have you observed in your experience?

See what Drew says above and look at the big test of prewetting posted elsewhere on APUG.

It improves uniformity and reduces the chance of air bubbles.