Past tense transportation: a reply

Huddleston (1977: 43), following some remarks by Poutsma (1926: 441–447), suggests that in (Huddleston's numbering) (1) I could have got the money easily enough there is past tense transportation (PTT), in that the CAN clause has ‘Unreal Mood (marked by the inflection on CAN) and underlying Past Tense’ and that the application of a transformational rule (PTT) allows ‘the Past Tense to be realized in the complement – by HAVE’. He proceeds to argue that the same is true of (5) (i) If he could have swum, [he would certainly have survived].