Programming in Lua book, will it help?

I have tried wiki, youtube videos, and even picking out scripts, but I cannot seem to progress from what I already know. I wandered the wiki and found the full "Programming in Lua" first edition available online. Has anyone used this, and has it helped you program in ROBLOX Lua after reading it?

http://www.lua.org/pil/contents.html

I could just use some standalone advice of personal experience reading this book, or someone to skim it and see if it's at any use to an amateur scripter like me?

Thank you.