They DO run security checks at Dover you know. Any lorry, van or car can be stopped and searched for contraband or illegal immigrants. What they are saying here is that in the short term they will not hold up lorries whilst the paperwork is sorted and any VAT/Duty paid - which used to be the process prior to 1992.
This is the good news. The bad news is that there will still be huge amounts of extra admin for companies not prepared for it and the EU should have to treat us as a 3rd country for any goods being exported. Lorries could well be blocked the other side of the channel - and who know what is happening with international driving permits etc.
Certainly no Tesco run for sausages and crackling pork for me any more in the event of no-deal Brexit as food product exports will be forbidden for normal travellers - takes me back to the foot and mouth epidemic where you had to throw your packed lunch in the bin at Calais.
"HMRC today said it had transitional procedures for importing goods from the EU through 20 British ports and the Channel Tunnel, which it would review three to six months after the UK's scheduled exit date.
“For a temporary period, HMRC will allow most goods moving from the listed roll on roll off locations to leave the UK port or train station before you’ve told us that the goods have arrived,” it said.
Importers must notify HMRC by the end of the next working day that the goods have arrived in the UK, and businesses will need to register for the simplified import procedure which will allow them to transport goods in the UK without having to make a full customs declaration at the port or later and paying any duty.
Under current rules for trading with the rest of the world, goods are not released from customs control until a full import declaration is made and the duty is paid or accounted for."