the "law" of reciprocal inhibition, like most laws, can be broken. it's says that if an agonist contracts, then the antagonist relaxes. for instance, if i want to drink from a bottle of beer, the i will use the flexors (e.g., biceps) of my arm at the elbow to raise the bottle. the triceps (the antagonist) do not contract. it would not be efficient. gripping the bottle in my hand however involves the engagement of both the flexors and extensors of the hand at the wrist (e.g., flexor digitorum superficialis and extensor digitorum longus). the motor control of the wrist muscles is "fine"... controlled as both the flexors and extensors are working cooperatively.

a more interesting example involves the lumbo-pelvic region.

http://en.wikipedia.org/wiki/Lombard's_Paradox -- here's another example

Jeff- My Seigs shows the extensor digitorum longus in the foot and the exenson digitorm in the wrist. Indeed if you were drinking a beer and contracted the logus you would be curling your toes up with your foot in mouth?? The action of the Superficialis muscles would grip the bottle.
Laws of nature can’t be broken or they are not a law – man made laws are frequently broken sometimes with consequences.

“Other paradoxes involve false statements or half-truths and the resulting biased assumptions”- from Wikipedia

“Lombard's Paradox: When rising to stand from a sitting or squatting position, both the hamstrings and quadriceps contract at the same time, despite their being antagonists to each other.” Also from wikipedia

Muscles go from 100% contraction down to 0% then begin extension up to 100% but at no time can they be doing both. Eccentric contraction ie lengthening under tension will allow that fine motor control but the muscle is still lengthening.
Enjoying the discussion and fine points. Best to you-H

Thankyou, I receive that.