everquset 2 plat, eq2 plat

Mentoring other players grants greater achievement reward for the mentor.
0-5 level difference: 0% bonus
6-10 level difference: 50% bonus
11-20 level difference: 100% bonus
21-30 level difference: 150% bonus
31-50 level difference: 200% bonus
51+ level difference: 300% bonus
This bonus is only applied to achievement experience gained through combat or loot items, not through quests or exploration.
Mentors also receive experience even if their apprentice has disabled combat experience.
I'm looking to grind aa, and I look at the chart above I'm wondering is there is a known sweet spot to level lock to grind aa, while I mentor another account. (I'm doing the raf but forget that for now) I just want to get the best aa for the mentor.

So there is no confusion ... the "sweet spot" im looking for is not a place but the best level to lock in and grind aa.

Is it better to stay at the 51 level difference?  When I mentor down to the 20s and 30s I can handle  2 or 3 levels above me which I assume gives me much better aa. But at the higher levels I won't be able to handle the higher content. Hard to say what will work better. Also, how much more aa do you get if you turn off combat expiernce for the apprentice?

Thanks!