Across

1. Can't Alfred feel the C function? Try taking B away. (7)
      IS AL NUMB                            -B  [int isalnum() is a C function]
4. Curse uncooked south oriental food violently (5)
           RAW      S      E        [anagram flag]
7. You know Alfred can't feel. Now you put your foot on him to drive him further? (5)
          [timepass!]                           PED     AL  [you push a pedal to drive something further]
9. Make efforts to move them. Now there's some useful work! (5)
   LOADS [you apply an effort to move a load, doing useful work in the process]
10. Measurement of time in milli nano seconds is a likely development in the near future. (8)
                   TIME IN   M    N      [sorry! no anagram flag]
11. Even Arlisto drew odd characters. (4)
    [draw odd characters from ArLiStO]
13. Alloy that's half unchangeable (5)
                 half of INVARiable
14. You'd be surprised if you heard - they fly straight - pole to pole! (5)
    TERNS [though their name sounds like 'turns', they fly from the north pole to the south pole;
    'heard' is a homophone flag; 'surprised' tells you otherwise;
    this clue breaks just about every rule!]
19. Launch into projectile motion (4)
    [the whole clue is just a definition]
21. Followed the way back to Terrace 'D' (8)
    [un-indicated anagram of RETRACED. sorry again!]
23. Not a stain on his character. (5)
    [second worst clue in the crossword! a saint has a stainless character]
24. They lead you from the edge to the centre of attraction. (5)
    [very lay person's definition of RADII!]      [timepass!]
25. He says, "An igloo serves a pygmy well.". What can be said of his screw! (5)
                 igLOOSErves               [this guy's screw is obviously LOOSE]
26. Small state becomes a bigger state. Are you in on this? (7)
      COUNTY                             R    ['in' is a container flag]

Down

1. Worsen a third important broadcast (6)
    [one-third of IMPortant]   AIR         [my favourite clue!]
2. Below chest found by sailor. Do big boys follow? (7)
                          AB    DO   MEN  [charade flag]       [I liked this one too]
3. What I should stick to when I drive (2,4)
   MY LANE [another stupid clue - wanted a two word answer; let it pass as a social message!]
4. Banish from memory and recall (4)
   [the whole clue is a not so technical definition of the technical term 'swap' in operating systems memory management]
5. The framework within which the artist works! (5)
   EASEL [meant to be a pun. SP, am I good enough?!]
6. Cause one South Arcot Regiment initially rearranged. (6)
         ONE S     A     R    [take first letters] [anagram flag]
8. First degree (6)
   LINEAR [whole clue is a definition]
12. Hesitantly ran East. He's now less distant. (6)
        ER     RAN  E      [anagram of NEARER]
15. Tod Cane is indisciplined. He's  __ _____. (2,5)
    NO CADET [anagram flag, which also suggests that he's no cadet]
    [The worst clue in the crossword. Kill me later]
16. A sustained ringing of bells, we hear. Now how's that for a request! (6)
    A          PEAL       [homophone flag] [how's that -> howzzat -> APPEAL]
17. Characterised by intense agitation (6)
    HECTIC [straight out of the dictionary]
18. Odd character. But not drawn this time. (6)
    [timepass; indicates there's no extraction to be done as with Mr. Arlisto.
    Just take the damn word at face value!]
20. Swing S around 11A, usually to capture (5)
          S  [11 Across -> ALSO] [you swing a lasso around something to capture it]
22. Catalyst and Oxidant, as chemists first would say. How does the common man know it? (4)
    C        a   O        [take first letters, sensitive to case!]     [CaO is lime]
    [I don't care whether or not it really is a catalyst or oxidant or both. Since we're past
    May 7th 2000, it doesn't bother me that I don't know. I request the chemistry studs to let this pass!]