The role of aspect and tense in counterfactual main clauses is discussed on the basis of both well-established and “new” data from Russian and French. In the first part of the paper, I show that the predominant use of the imperfective in French counterfactuals is arguably “fake”, i.e. without semantic impact, while aspect in Russian is “real” and retains its normal meaning in the same counterfactual environment. In the second part of the paper, the focus is shifted to certain irrealis contexts where a fake imperfective – without conditional/subjunctive morphology – is found both in Romance and Slavic. This surprising “counterfactual imperfective” in Russian is given a purely competition-based pragmatic explanation, and it is shown how pragmatic strengthening and the development of aspectual implicatures arises through associative learning in diachronic steps. Both in Romance and Slavic, past tense morphology in this construction is licensed by a real semantic past in the input context, i.e. a kind of past tense anaphora. This is different from ordinary counterfactuals where one layer of past tense is “fake” and the irrealis hypothesis can be non-past.