I decided to try this for the first time the other day (on my dad's Max) and it went alright except for a couple of small problems:

I could only reach so far in with the towel and toothbrush and I felt like there was a lot more grime further inside. Is there a method of going in any further?

The throttle body cleaner started melting my gloves and toothbrush while I was cleaning. So it eventually got all over my hands and I had to keep replacing my gloves. I have the vinyl ones. Any special gloves that I should buy for when I do my car?

And by the way, the car had some idling problems before that completely went away after I did this. It also used to shake after you would suddenly step off the gas while driving and it doesnt do that anymore.

 

You can use a weight to hold the gas pedal down to open the throttle to try and get a little bit farther in there, or you can hold it open by hand too....it's tough to get really too far into there, but that'll help if you didn't get into there already.

I personally didn't even use gloves...I folded up two towels and put them under the TB opening to catch the goop, sprayed the hell out of it, and kept wiping with more towels, over and over again....i had a few packs of microfiber towels that hadn't been used so i did that instead of a toothbrush....used about 6-8 towels this way, and then washed the crap out of my hands for a good hour or so...and then again the next day, and then the next day

As for your results, that's pretty much what's expected when you clean it, glad your idle and shaking problems went away, mine did after i did mine!