I am using a condenser mic on my amp, and wanted to get sustain for passages on a ballad. I have had an E-Bow for years, but rarely touched it, so figured would be a good time to try it out. I actually do not want the legato sound, so began using a thumb pick, which has made for awkward positioning but works. A couple issues came up -

1. The humbuckers are very sensitive, but passive, so I cannot get a harmonic to release, yet have seen videos of people doing this (i.e. shifting back to a fundamental).
2. I actually played with letting the amp provide the sustain, but did not give a desired "even" effect. Even using the pick, I was still getting legato effect on a few notes (hammer-ons/pull-offs), and this is what I am trying to avoid.

Being in a hurry, I ended up looping that section and swapping techniques (pick, fundamental ebow/pick, harmonic ebow/pick), and ended up comping these together (cheated). Then it occurred to me that this must be possible. Is there a "best" technique to get a harmonic to release? Especially with the harmonic setting, I cannot achieve this even pulling the ebow completely off the guitar (having the pick in use also limits how much the right hand can move).

Picking the harmonic (fundamental or higher) to resonate is largely a matter of moving the e-bow away or toward the bridge. You can get a lot of control that way. If you just leave the e-bow in one position, you're not using it to the best effect.

Thanks for the feedback. That is what the videos were showing, but I cannot get it to. I need to play with it more for sure. I didn't see a single video of anyone using a pick, and that makes it awkward to slide down the heel of the E-bow to get a light palm mute on the bridge. I think the amp may have also been a bit too close to a normal feedback level, so the E-bow just gave it that extra kick and the amp took over from there.
 
I am not sure what frequency focus the guts of the E-bow are on, but it takes very little to pull the A5 harmonics on the B-string especially. The other interesting thing is in a sonogram view of the clip the harmonics do not "look" very different in power (the A5 is singing in the green box). I had sent Carvin a question a while ago about the EQ response of the amp, but I never expected an amp to throw so many harmonics (all the way up to 18K on that part)... I thought the speakers (2x12") were too big for such? These are all single notes from the amp into a large diaphragm condenser.
 

I don't know which speakers are in the Carvin, but 12" Celestions have some output at surprisingly high frequencies. It's 25-30dB or more lower than the mids but it is there.

If the ebow is building up a lot of high harmonics then might that explain the plot, especially if the cone is centre mic'd? I don't use an ebow myself, for sustaining attack-free slidey stuff I use a Daevid Allen/Steve Hillage/Dave Brock style glissando technique which can be extremely bright unless the guitar tone is rolled off.

I've used an e-bow quite a bit - not with a pick, true, just with hammer-ons. Using a pick would - I think - bias towards the fundamental frequency of the string, so if you're experiencing that, I'm not surprised.
 
Here's the thing, though: It's always a little hit-or-miss. I have different guitars and different strings, and different pickup placements, and they all behave differently from one day to the next. Maybe more practice would help but basically, I always record several takes and keep the good bits. 
 
And a fresh battery always helps.

I ended up using the same version I had when I made the OP. I used it for a 20s addition to the BOZ Remix Contest (at 1:20 in the track I submitted). Even at 25% power with a gain of 2, the amp was throwing some powerful harmonics in this section (it is mixed around -19dB). Mic placement was about 8" off the floor midway between the speakers at a spacing of around 2 feet.
 
Making that addition may be a kiss of death, since I am sure Greg Johnson (who wrote, tracked, and originally mixed it) is one of the judges; but at least can be an example of "E-bow with a pick." I did a lot of first time playing with this mix, so definitely had my fun with it.