For chamber blocks its now overhead --> overhead and thrust --> overhead or thrust --> thrust
ie incoming overhead attack, chambered with an overhead, incoming thrust can be chambered with overhead or thrust.
As was already said with the timing of them if someone is doing feint left, attack right at "normal" speed, if you swing to chamber block the left feint, they will have to block or be hit. But if they do a feint that is just a block motion and is really fast, and swing again, you will get hit, or they can do the left/right feint super fast and sometimes connect first.
Also as ruth said, which I observed ironically enough dueling akmar who was doing overhead feint into right attack, even though his feint in this case was 'normal' speed, trying to get my overhead chamber block swing to hit him couldn't connect first as the overhead swing is slower. I've since seen this play out a bunch of places. The short of it is really that if you are playing a person who is chambering you, you can sort of be 'safe' from the above described style attack by starting with an overhead, not that it is super helpful, just a small detail to keep in the back of your head.
Anyway I like guide. I actually in my head would think of the term 'deep feinting' as swinging and pulling back at the last minute, but it also works in the context you picked for it too
I will add link to it in infantry primer in the dueling section.