Does the time played stack in a class when in a vehicle in battlefield 3?

There are many awards that players can strive for in Battlefield 3. A few medals are for a decent amount of time played in a vehicle, emplaced weapon, and class.

If I were to play with the Assault kit, and get into a tank, would this add time to both the assault played and time in a tank? (for this example: Tank Service medal & Assault Service medal)

I know this:

If you gain score in a tank, the points do not count towards the assault class. It will count towards the overall tank vehicle score.

Although, total time played will build for the RU / US Service metal, regardless of which class or vehicle you play in.

If I were to play Assault and play defense in an emplaced weapon, would both times played build synchronously ?

Solution 1:

I just checked my Battlelog and added up all of my kit score times + my vehicle times and the add up to equal my total play hours. Also I looked at the kit required medals the hours match these times exactly.

Upon further observation, my total vehicle time is 19 hours, but when I add up all time spent in VEHICLES meaning just tanks/planes/helicopters I fall short which leads me to believe that time spend in stationary equipment does in fact count double but time literally in vehicle only counts towards that vehicle. I think this can be attributed to the fact that vehicles have unlocks whereas stationary defense does not.

So it seems if your feet are on the ground then you get time towards the kit, but when you are in a vehicle the time only counts towards that vehicle time.

"Although, total time played will build for the RU / US Service metal, regardless of which class or vehicle you play in." - I also don't think that this is correct because my time played as RU is 44hrs and my US marine is 43 which is 87 and my total play time is 107 hrs. Then my vehicle time is 19 hours so 87 + 19 = 106 (estimated numbers).

Clearly DICE had a strange method of computing times and how they will count.