For years I've carried a Gerber bolt action knife. It's usually in my pocket these days but for a long time I carried it in the nylon Gerber holster upside down on my belt. When I needed it, I'd just drop my hand against the velcro and it would fall into my hand ready to use.

Never had a velcro failure or dropped the knife.
It made the perfect carry when you had one hand full or something else.

Anyone else use that technique?