Willis (2011)

• Willis, D. 2011. 'Reconstructing last week's weather: Syntactic reconstruction and Brythonic free relatives', Journal of Linguistics 47 (2):407-446.

 Abstract:
 "Lightfoot (2002) argues that syntactic reconstruction is rendered impossible 
 by the lack of any analogue in syntax to the traditional notion of the 
 phonological ‘correspondence set’ of the Comparative Method and by the radical 
 discontinuity caused by reanalysis between successive grammars. 
 Alice Harris and Lyle Campbell, in various works, have defended the notion of 
 ‘syntactic pattern’ as the analogue of the correspondence set, arguing that 
 patterns can be compared across languages, with innovations being stripped 
 away to reveal aspects of the protolanguage. 
 In this article, I argue that syntactic reconstruction can be carried out while 
 maintaining and indeed utilizing core notions in generative approaches to 
 syntactic change such as the central role of reanalysis and child language 
 acquisition and the distinction between the abstract grammatical system and the
 surface output of that system. Reanalysis itself is constrained by the fact that 
 both pre- and post-reanalysis grammars must be acquirable on the basis of the 
 same primary linguistic data. 
 This imposes limits on the possible hypotheses that can be entertained 
 (‘local directionality’) even in the absence of any crosslinguistic generalizations 
 about patterns of change (‘universal directionality’). 
 This approach is then applied to aspects of the syntax of free relative clauses and 
 negation in the early Brythonic Celtic languages (Welsh, Breton and Cornish), 
 showing that non-trivial reconstructions can be achieved even where the daughter 
 languages manifest significant differences."