Setting the SMPTE start time to 1 hour first is definitely required in Logic for example and as
Freddie has pointed out it might be the case in Sonar as well. But this does NOT apply to all DAW's I am pretty sure. For example I use Studio One 2 PRO. If I import a movie that say I might want to start at 1 minute 30 secs for example I need to set that time exactly as is. eg 0 hours 1 Minute 30 secs. (As it should be IMO) If I set the start time for 1 hour 1 minute 30 secs the movie will not play until the time line gets to 1 hour, I minute and 30 secs. Hence the movie will just sit there and do nothing for 1 hour.
The 1 hour thing was to identify different reels in the old days working with film etc. Apple have adopted it because it is the way Final Cut Pro works I am pretty sure and they wanted Logic to agree with it.
So a good rule of thumb is maybe start by not adding the one hour unless the DAW in question does not seem to work (well) or the video will not play at all then put the one hour in and see what happens. Unless one has amazing and detailed knowledge about every DAW there is, one perhaps may not know how it works in every DAW.