I recently had to go to London (tier 4) from my home in a tier 3 area.
I bought a train ticket as normal, went to the railway station, got the train to Paddington, then got the tube across London and went to where I needed to go. A few hours later i reversed the trip and at the last stage got a taxi home.
At no stage did I see a police officer or did anyone ask me why I was doing the journey.
Should we start trying to enforce the restrictions we have?