I always give my plant roots a vigorous "massage" to untangle the roots, and clip some back if they are tangled. I don't believe it has a taproot. Found this info:

Skullcap (Scutellaria lateriflora)
Part used: Aerial parts
Medicinal use: Used as a sedative in the treatment of anxiety, insomnia, nervous irritability, and some forms of depression. Also used for headaches, as a diuretic and as an antispasmodic.
Growing tips: This herbaceous perennial plant likes moisture, fertile soil, and cooler temperatures, so plant in a low-lying area with full sun or partial shade with 8-12" spacing. It can be cultivated by seed, cuttings, or root divisions, and spreads like mints.
Harvest tips: Harvest when it begins to flower, clean soil and other debris off plant, and dry immediately. One cutting in the first year followed by two cuttings in consecutive years can be expected.
Enjoy! Lynn

Well, since you are in zone 10, I would... be gentle, it will go into shock a little... usually, if it would be going dormant and dying back, I'd say no...

I haven't really broken up the root balls of anything else I've replanted, but this little plant was pretty darn compact. It's not a single plant/stem, more a forrest of sprouts. I'm betting it's pretty well established, so I'll break it up GENTLY...just a LITTLE.

Thanks for the reply and the info, both of you!