Havnt seen this myself personally, have heard it referred to... ??? To be sure my sources aren't exactly firm on it...
But I understand it to be some pretty severe forces involved to get the subframe to move, curbing/driving up a side-walk at 5 t 10 K/hr wont do it, but 50K/hr mite...
But basically, they loosen the bolts/nuts, then realign it and do up the bolts/nuts...
Yeh i did take this into consideration but as he has had all the control arms and hub replaced would suggest he hit pretty hard.. But yeh, through it up on a decent alignment machine and get someone that knows what they're doing to have a have a look at it, that why you can check ya SAI, Included angles etc, see how much setback if any etc..