I've been reviewing a final table I made which was live streamed (thinly veiled brag), and the guy to the right of me continued to bet 50% of his stack instead of going all in when he has 10-15bbs. He's a good player with results, so there clearly is well thought out logic behind this, but I'm a fish in regards to this aspect of the game. Is it purely a way of just balancing your value and bluff shoves, so you're not dominated when all in with hands like A5?

And if so, what range of BBs should you be employing this tactic, as opposed to just pure jamming your range?