Understanding his instincts
The process of getting acquainted with casting arrays was a tedious one. After his initial 'Hello World' experiment, Lex no longer tried to cast any original arrays, and instead repeatedly cast the warming array he first tried. After successfully casting the array ten times, he paused to take note of his progress.
The first thing he noticed was that, for now, he was stuck being extremely slow at forming an array. If he tried to speed up writing a character even a little, the character would be disrupted and all the spiritual energy would disappear. That was only the case in this simple array, as for more complicated arrays, instead of disappearing, it may result in an adverse reaction.