personally i use a /click macro for my 1 button tanking macro and it works great.

PHP Code:
"The Big Button"
/click BT4Button109;leftbutton
/click BT4Button110;leftbutton
/click BT4Button111;leftbutton
/click BT4Button112;leftbutton

//Macro 1
/castsequence reset=9 Avenger's Shield,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

//Macro 2
/use 13
/use 14

//Macro 3
/castrandom Cleanse, Exorcism, Hammer of Wrath, Avenging Wrath, Hammer of Justice,,,,,,,,,

//Macro 4
/startattack
/castsequence reset=9 Holy Shield, Judgement of Wisdom, Consecration, Hammer of the Righteous 
it works great for me, my pally is only 73 so i don't have a couple spells in there and it still needs a little "fine tuning" but it is almost perfect for me. I could remove a couple "," from the 1st macro because at the rate i push my button it always fires about 1-2 seconds after it is off the CD but that doesn't bother me much.

just thought i would share sens we are on the topic of a "1 Button Pally Tanking Macro", maybe it will be of some use to somebody ^_^

~YYF

EDIT*
strange not sure why the text changed colors, al i did was copy and paste, so that was not purposeful at all lol

~YYF