I like the dual chains.
A > B > C
A > D > E

With the booster on 'A'.
Even though the A > B and A > D chains are invalid for RAF... the B > C and D > E chains are both valid, so the boosted accounts BCDE all get RAF bonuses.

And because A is linked to the dual chains, they receive granted levels.



For RAF to work, you need to meet all of these criteria:
a) Accounts directly RAF linked;
b) Characters grouped together;
c) Characters within +/- four levels;
d) Quests and/or Mobs killed, not greyed out for either toon;
e) Characters both at 79th or lower;
f) Within a certain range of your RAF partner



If you 'boost' four toons on BCDE, with A.
-- E grants two toons to D
-- C grants two toons to B
-- D grants two toons to A
-- B grants two toons to A

Then because B received two toons, they can grant one more to A.
And same deal for D, granting one more to A.

Special note: You can grant one level, for every even level your toon gains from 2nd to 78th.
So if you start at 55th as a Death Knight, that is (56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, and 78)... 12 granted levels in total.
Everyone else grants 39 levels...

You're the same percentage into your levels, when the granting is done, as before it was done.
39 + 39 = 78, not 80.

So if E is granting levels to D...
You would make a toon on D, and level them to 2nd (and be as close to 3rd as possible)...
If you accidentally reach 3rd, via exploration experience, you'll want to kill a few things and get almost to 4th.
Anyway, 2 + 39 + 39 = 80.

To grant a level, you need to be higher level than the recipient, and directly RAF linked (you referred them).
Also they cannot be 80th or higher.
So an 80+ can grant a level to a 79 or lower.



A group that can do LFD, with all of the bonuses, will level basically the same pace as a boosted group.

But you'll need one toon that can spec tank (even if you don't).
And a different toon that can spec heals (even if you don't).
The other three can be anything.

You'll also need to actually be able to do the dungeons.



A booster is the other option.
If you're brand new, you'd quest or do dungeons, with an initial group that includes a toon who can boost well on 'A'.
Those are generally Paladin or Druid, but almost anything else will work to some degree.

If you're starting on a brand new server...
You could server transfer your single booster, with some resources (bags, gold, etc)... to play with other boxers in a boxer guild...
And boost away...



The reason for the double chains, is the cascading of granted levels.

For every hop in the chain, you need to exponentially level 2 toons, for the granted levels to add perfectly to a full toon.
So with two hops, you get 2^2 (2 x 2 = 4).
With four hops A > B > C > D > E, you get 2^4 (2 x 2 x 2 x 2 = 16).
Meaning with four hops, and a maximum of 11 toons on an account, the cascading levels will not work... so you won't end up with a full toon, based entirely off of granted levels received... without wasting a lot of those granted levels.

But the 'anchor' account receives nothing.
So A > B > C > D > E... has one achor account, 'E'.

While the dual chains:
A > B > C
A > D > E
There are two anchor accounts, 'C' and 'E'.



Still with the dual chains:
A > B > C
A > D > E

You boost four (or do it twice, for 8 toons).
You end up with:

A: Booster + Six toons, all granted.
B/D: Four boosted toons + 2 granted toons.
C/E: Four boosted toons.

If cash is available, you can do transfers to even the accounts out some.
RAF is essentially choosing to spend cash to save time.
Non-RAF is choosing to spend time to save cash.
But you'll decide where the happy medium lies...