ES's synergy is Telek. But it doesnt state what bonus it gains from it. I made a light sorc on NL, and put 14 into tk, and made a light sorc on ladder and put only one. Ladder puts out more dmg, but nl plays a bit better, seems like it can tank more. Can someone clarify what TK does for ES? Thanks.

Im not sure but I think what it does is lower the mana it takes away when you get hit...
I really would look it up but Im getting Problem Loads page everywere!

So basically it acts as a DR?

Each point in Telekinesis makes Energy Shield's damage absorption more effective. By default, for each point of damage absorbed by Energy Shield, 2 mana points are deducted - a 200% ratio. Each hard skill point in Telekinesis makes Energy Shield 6.25% more effective. For example, with 8 points in Telekinesis, 1.5 mana points are deducted for each point of damage absorbed - a 150% ratio. With 16 points in Telekinesis, one point of damage absorbed equals one point of mana loss - a 100% ratio.

-Arreat Summit (http://www.battle.net/diablo2exp/skills/sorceress-lightning.shtml)

GG. Thanks.

The only issue with this ofcourse is that if your mana pool / regen rate isn't high enough, you'll be hit hard a couple times and can't teleport away.

Most beneficial with Insight lvl 17 merc imho