Thanks Malone, think your parsing of this clue is right. I had never heard of blastit, and went for a quote from 'To a Louse'. Overthinking here - Myops makes me do it! Was always bad at anagrams!
I'd never heard of 'blastit' itself, but I remember 'sleekit' (in the Mouse poem) so maybe the '-it' ending is quite common? At least you've got some reasoning - perhaps correct - for your answer!