Maybe "semi" means you're taken to a likely area, and have it explained to you where you're most likely to find game. This can be from a base camp "way out there", or from a ranch headquarters, I imagine.
Fully-guided would mean the guide accompanies you during the hunt.
There's no one size fits all in this. Different outfitters have different styles, and can tailor the "baby sitting" to the customer's needs.
You're from BATFE? Come right in! I use all your fine products!