So you claim that 1400BTC was moved in a few seconds? Under 5 minutes if I'm feeling generous? Let's have a look...
For the entire hour from 15h00-16h00, volume on bitfinex was only 3000BTC. Let's see if anything exciting happened in that hour on closer examination... Largest 5 minute volume in that hour was 967, right about the time of your post (15h45-15h50). If we go further into the 1 minute interval within this 5 minute period the largest volume was 302BTC...
You can draw your own conclusions... It certainly is possible for 1400BTC+ to be moved quickly, but I'd hazard that 99% of the time there is a good portion of the wall that simply gets cancelled
Check your time vs chart time
it was here, in 1min chart at 9300 total moved 2k

