ya... tried before and it is ok. not sure what you mean by lag...

tried between note and sgs2.

update1:
oh ya... i was kinda surprised there's an option to actually record the video call. you can actually record the other party... yes, i tested and it works. i think the format saved is 3gp though.

update2:
so be careful and dun be notti when calling samsung note owners (not sure if the function is available on other phones). never know if your video call is being recorded. <-- not sure if the other caller gets prompted abt the video recording taking place. ya... could be a privacy concern for some.

i think pass-thru and tethering is different:

1. USB tethering is computer/laptop using phone's mobile network - yes, work on both DHD and Note.
2. Pass-thru is Phone using computer/laptop's internet connection via USB cable - work on DHD but I dun think Note has this function.  Correct me if i m wrong.