Full Idea
One of the advantages of the move from nomological to mechanistic modes of explanation is that the latter allows for explanations involving exception-ridden generalizations.
Clarification
'Nomological' means lawlike
Gist of Idea
Unlike the lawlike approach, mechanistic explanation can allow for exceptions
Source
Stuart Glennan (Mechanisms [2008], 'regular')
Book Reference
'Routledge Companion to Philosophy of Science', ed/tr. Psillos,S/Curd,M [Routledge 2010], p.378
A Reaction
The lawlike approach has endless problems with 'ceteris paribus' ('all things being equal') laws, where specifying all the other 'things' seems a bit tricky.