it is really awkward, not sure about ambiguity though, if you remove that section the sentence goes : Rising inventories can lead to production cutbacks that would hamper economic growth. which is a statement, the commas are usually used when inputting explanation or supplementary information. so for the "when unaccompanied correspondingly by increases in sales", it is awkward in a few ways. first it would be nicer if there's a by after unaccompanied. second, unaccompanied and correspondingly are similar in meaning here and quite a bit of denial logic trap for an explaination. it is trying to say "when it is not accompanied by increases in sales" or "when it is not correspondingly matched by increased sales" or simply "when it is not matched by increases in sales". the awkwardness comes from double description of the relationship for the increase of sales and the un-accompanied's denial logic and correspondingly's complementary logic is probably the ambiguous bit. since it's kinda annoying to realize if it is unaccompanied or is it correspondingly. it would also work if they substituted correspondingly with accordingly "when unaccompanied accordingly by increases in sales" hope that helps