Puzzletome Crossword Puzzles

April 2017 Monthly Crossword
Alternating Syllables

The thematic asterisked clues are a bit offbeat. They have no definition, and in each case are constructed as alternating syllables for the two entries. These four entries consist of the protagonist, two things he did and one thing he used. A further thing he did (undefined, but otherwise normally clued) is given at 14/27. Additionally, seven consecutive clues contain extraneous words that define the theme both initially and in full.
Grid
Across
1,29* Error say space firm, most of the time; assistant thanks participating troop leader mid air over Ecuador borders (11,11)
7Graduate's major conclusion reveals measure of strain? (3)
9Years taken up in piano education (3)
10See 26a
11Started off with Abba, The Beatles and Queen maybe? (7)
12Dominate arrangement of Oliver before beginning Evita (7)
13Diseases principal meaning clear in beds (10)
16X mark is spot revealed (4)
18Record of sonata performer (4)
19They must be transported in Spain with sail barge (10)
22Flatten note (sharp) - catching up after final performance with quintet (4,3)
24A target for competing crews? (7)
26,10* Pedigree Glaswegian heard on Monday: "Jack's work with one (getting nothing back) has failed" (11,11)
27See 14d
28Easy listening starts with a bit of free spirit (3)
29See 1a
Down
1Is critic finally on record (the jerk)? I doubt it! (7)
2Musical piece lacking in profit? (5)
3Brawn's back half behind boast building block (8)
4Sounds of a bird sound - bats sounds? (9)
5Very enthusiastic about incorporating reading of overture (5)
6Makes investigation around circular loops (6)
7Evening dance (comprising one also known as India) contained instrument (9)
8Glasgow team exchanging one for one to get church players (7)
14,27Plan with member to contain a flare up (5,4,3)
15She has rhythmic ideas and he is retro active (9)
17American saint gets one grand to cover amateur cross marks? (8)
18Selection at rest generating Lego frame (7)
20Vermin carrying seed all over tempo shock (7)
21Brush aside inspiring finale as orchestra leader enters valley (6)
23Belief principles that elicit new musical experimentation techniques (5)
25City elevating routine in entertainment (5)