The Man That Was Used Up

I have to apologize for this puzzle. It lacks symmetry, and occasionally has two unchecked squares in succession. (Chalk it up to my inexperience in making crosswords.) To make it up to you, I added a special bonus: a theme. Six answers have something to do with the title of the crossword, and one more answer has something else to do with it.

Across

5. Seven felt sore, disturbed, calm despite a tense situation (6,2,5)
10. Youthful nanny provides beef shank, perhaps (4)
11. Crow Indian site for sliced turkey, for example (4)
12. Tendency to speed: immediately after beginning is end (4,4)
13. Spooner’s title for an apocalyptic tome (3)
14. Musical hasn’t a cast left? That causes a seizure (4)
16. Ability to handle prison food, say: criminals got up to speed (4-4,7)
21. A de-facto capital: a place to hide away (4)
22. Leftist men ail Lew Rockwell, manifesting what’s totalitarian (9)
24. Commenced marketing for legalese leader, in jargon (6)
25. Retro sconce, perhaps, illuminating a slightly hidden area (3,5)
27. Author, in 1839, of odd prose (3)
28. Giving Nature trouble with the Fargo old (5,2,4)

Down

1. Gives out answers to the audience (5)
2. Nice to have something to breath: it contains very odorous particles (5)
3. Up-do in rows? Whatever (5,2)
4. Step and work endlessly for tone (5)
6. Persuasiveness urges violent craziness (6,6)
7. Order a car (4)
8. A rock band: waltz-time emulators (3)
9. Dead, and others, rising (4)
15. Nut canape’s top half is on the bottom; its bottom third’s on top (5)
17. Total Recall prosecutor, defense, and criminal pout (3,2,2)
18. In Palestine, a rabbi’s inability to hear subtext (3,3)
19. Widow, New-England-headed for celebration, becomes spiritual person (3,4)
20. Robot in a neural network, say, in the heart of newsgroup posting (7)
23. Surround a girl with love (5)
26. Block the game-show panelist from having a loss, at first (3)