Puzzletome Crossword Puzzles

January 2013 Monthly Crossword
Additions And Removals

This month, a set of six appropriate items are given in logical order, although this order varies in many places. The twelve asterisked clues comprise six that must be modified by removing one of the items before the clue makes sense, and six that must be modified by adding one of the items. There is one instance of removal and one of addition of each of the six items. Two of the items require extending for differentiation purposes. All remaining clues are normal.
Grid
Across
1 Estimated distance around cooked plaice with unique ingredients? (11)
7 * Hall of Fame - third American returned there (3)
9 * Incompatible one to seminal fiction (5)
10 Recognition of, for example, this year's objective (9)
11 Single seater on The Strand? (4,5)
12 Promote far-fetched tale about treasure here? (5)
13 * Druse forte contained existence (7)
15 Item 1 (4)
18 Item 4 (4)
20 If I get in for five then? (7)
23 Up before court (5)
24 * One interjected to flag male led dance (9)
26 @#$%! old boy's taking space in capital (9)
27 Drink jingle sung with energy (5)
28 Item 3 (3)
29 * Oft thy pact is broken with me (11)
Down
1 * Singular beat - remove old away (5,3)
2 * Showing nice building around central convent with defaced arch (8)
3Compound number 102 with electrons? (5)
4 * Meadow monk to develop flow (7)
5 Unknowns mostly push into one's own brewing (7)
6 * Pay retains restless peers with love for criminal (9)
7 Turn a leaf of bristles? (6)
8 Item 5 (6)
14 * South and North mixed up with East extremely serious for Earth (9)
16 * Switching hour for maiden hiding busy time (8)
17 First name as shown in law? (8)
19 Truth or lie mars outcome (7)
20 * Friend to badly mar ancient Syrian city (7)
21 Item 6 (6)
22 Exuberant agreement to enclosure (6)
25 Item 2 (5)