So I keep seeing this misused, join with me, and comment on your own pet peeves about the same or similar subject:
Competitive = directly proportional to the average skill difference between all players present
Competitively Determinate = effective at evaluating the best competitor at an event
FluffBunny40k, where the ultimate winner is determined by who can dance best, but where everyone is almost identical in skill and army list ... vs. NOVA format (or, in comparison to that, ANY format) ... one is by nature Competitive (The first), the second is simply Competitive Determinate.
MOST 40k events are COMPETITIVE, made more so with larger crowds and more rounds, where your later rounds are probably going to be pretty "close" in terms of skill matching.
NOT all 40k events are competitively determinate.
NOW EAT SUM LEFOTVERZ