Quote Originally Posted by MorkaisChosen View Post
The bonus isn't stacking, it's overlapping, but the cap is increasing, and since each Chicken Spam Attack allows you to increase your CL arbitrarily high (limited only by the cap), it goes up to the new cap. Recast, get a higher cap, get that cap as CL, recast...
Yes, I know. That's why the second casting had any effect at all.

You cast it once and go to the cap. The cap is +6.

You cast it again, and the cap is now +9. Go to the cap and your total caster level is 22.

You cast it a third time and the cap is now 22/2 = +11. Go to the cap and your total caster level is 13+11 = 24.

Fourth time the cap is +12, for a total of 25.

All subsequent castings have a cap of +12 unless you can somehow boost your caster level to 26 or higher - and the field itself won't do that because its cap only gets you to 25 with your base of 13.