Hello,
First, i'd like to apologize for my poor english
this isnt any game-breaking guide, just a little hint for Transmutation and Potion masters.
Im usualy transmutation master, but every second week or so i make some flasks for myself (got more characters, so i need a lot of them), but not every time is elixir master around and after all, im alchemist myself, so i fly to Netherstorm to Zarevhi, unlearn transmutation mastery, fly to Lorokeem to learn elixir mastery, make some flasks, unlearn elixir mastery and then back to Zarevhi for transmutation mastery
TL;DR version:
1) Buy/farm a lot of herbs and volatiles for flasks (i usually make 60-80 flasks)
2) Unlearn your current mastery (Zarevhi for transmutation, Lauranna Thar'well for potion) for 150g
3) Fly to Shattrath City and visit Lorokeem, learn Elixir mastery for free
4) Make flasks and enjoy extra procs
5) Unlearn Elixir mastery
6) Travel back to your trainer, re-learn your former mastery
7) Keep extra flasks for yourself, or sell them, but NEVER put all of them to AH, just a few every time, somebody will untercut you anyway, best time is evening before raids
Proc rate for extra flasks is around 20% and with current prices 3 flasks will cover your expenses for re-specing, 4th and others extra flasks are profit
As i said, its common sense, almost every alchemist knows this, but for somebody it could be new and usefull