I cannot praise/recommend BLW enough!!
It's nothing new, really...just has a "name" now. We started when DS was about 5.5 mos by following his cues. We had lots of skepticism from family and lots of worry that A) he would choke and, B) he would only ever know to eat things with his hands (this was MIL, bless her).
He did gag quite a bit at the beginning, but something you will learn through reading up is that a baby's gag reflex is further forward on their tongues. This means it is triggered sooner so they can work the food away from their throat (so they WON'T choke) and most times, they carry on eating it. In my son's case...ALWAYS went back in the gob! Best rule of thumb is to follow their lead, so if they're not bothered by it, carry on. Also, the more calm you stay about it (even if you're freaking out in your head) the more calm they will be/deal with it.
We didn't do any purees at all and a couple weeks in, he was having Sunday dinners at the table with the family. Still loves his Yorkshire puds now at 19 mos! Hehe.
As far as anything on a spoon, I would pre-load the spoon (yogurt, for example) and hand it over to him. He knew exactly what to do and YES it was messy, but that's all part of the learning process.
I blogged (and still blog) about many things with him, including our BLW journey if you'd like to see...
http://meguk365.blogspot.com/search/label/BLWAlso, what helped me was watching You Tube videos on BLW to prepare myself for how it would look/sound. There is also a BLW group on Facebook.
Hubby and I always say it's the BEST decision we ever made as first-time parents and to look back now, our son is 19 months and it's a lovely feeling to sit at the table together and enjoy our meal(s) warm!!
Good luck! x