But... I read quickly through it, and I saw no meta-analysis. Just a literature review. What's with the post title?

You're right. I don't remember why I wrote "meta-analysis". (Probably because it sounds fancy and smart). I updated the title.

Is this referring to effect sizes or p-values?

p-values.

Eh. Absence of improvement != damage.

True.

...Randal 2004 didn't find a statistically-significant decrease...

No. In Randall et al. (2004) participants in the 200 mg modafinil condition made significantly more errors (p<0,05) in the Intra/Extradimensional Set Shift task than participants in the placebo and the 100 mg modafinil condition. (The 200 mg group made on average around 27 errors. The 100 mg group around 14. The control group around 17 errors.)

Actually, you linked to a different study. The results can be found in the complete study I linked to. I can upload it if you want to see it yourself.

Reprinted from Baranski et al. (2004) without permission.

Every single graphic in this whole thing is reprinted without permission, to tell the truth. (Is this a problem?)