DFA wasn't really all that common a tactic because it royally screwed you over, even if you pulled it off.
However, in this instance, it was valuable because we pretty much traded a Highlander who was already heavily damaged for a Daisho... so a 90 ton heavily damaged mech for a mostly undamaged 100 ton Clan mech... I'll take that trade-off any day.
Mind you, DFA was slightly more common in team play, where you weren't betting the outcome of the fight on a 1 in 6 (twice) chance, since your buddies can theoretically cover for you, but still...
It may not have been that common, but it's one of those things that you always remember. "Yea, there was that one team we went up against... damn Highlander dropped right on top of the Marauder..."