The question is, how many sets of alts are you going to boost.
And where would you like the granted levels.

To get 3x exp's, we need all of these to be true:
a) Accounts are directly RAF linked, and are grouped together.
b) Toons are +/- 4 levels of each other.
c) Toons are both level 59 or lower.
d) Mobs are not grey to either toon.

If you were to link:
X -- A -- B
X -- C -- D
And X were a level 80, while ABCD were level 10's.
The X -- A and X -- C links do not provide RAF.
But the A -- B and C -- D do, so they get RAF.
Conversely, X -- A, X -- B, X -- C, and X -- D, are out of luck.

A further consideration is granted levels.
For every even level gained, a toon later in the chain can grant one free level to the preceding account.
This is limited to 30 levels maximum at 60th.
And to granting to toons lower then yourself (ie highest boost is giving 60th to a 59th level).
It is important to note, you remain the same percentage into the level, so you could be 96% into 3rd and receive 57 granted levels and be 96% into 60th (ding 61st on exploration exp's enroute to Hellfire).

Granted levels cascade.
Take for example:
X -- A -- B
X boosts A+B to 60th.
A gives 30 levels to X, B gives 30 levels to A.
A now had a level 30, which can give another 15 levels to X.

However, you can only grant to a toon who is lower then you.... so for every link in the chain, you need to boost (x2) toons to take full advantage of this.
For example:
X -- A -- B
Boosting two toons on A, gives A the ability to grant 60/2 + 60/2 = 30 + 30 = 60 levels... and B can do the same to A.
It is in your best interests to concentrate granted levels into single toons, for the subsequent granting of levels based on levels received.
A received 60/2 + 60/2 = a full 60th from B, but can only cascade 30 additional levels to X.
A is one link removed from X, so one link x2 = two toons boosted for maximum gain.
B is two links removed from X, so two links x2 = four toons boosted, for the cascade levels to equal a full toon on X.

You have a lot of options on linking.
X -- A -- B
X -- C -- D
(This has the most granted levels on X, assuming you boost 4 or 8 toons, but B/D don't receive any granted levels).

X -- A -- B -- C -- D
(This is the most total granted levels, and an even number of teams is ideal. Either 2/4/8/16, depending on how well you'd like levels to cascade -- note 10 toons per account max; D receives no granted levels).

X -- A -- B
......A -- C -- D
(This will have most of the granted levels end up on A, with no granted levels on B/D.)