Any question answered...

This part of the CSH has always baffled me. The sign after the Vauxhall Bridge junction heading west indicates the cycle lane only applies 7-7 Mon-Fri (rush hours). Outside these times I assume it is ok for traffic to use the lane regardless of the solid line?

Remember that the purpose of these facilities, in common with bus lanes, is to reserve space for more space-efficient modes in the morning peak hour, and to some extent in the (less concentrated) evening peak. This is because in London traffic flows are very unevenly concentrated, largely radially into a disproportionately small centre. Outside of peak hours, this constraint disappears.

I've never understood this at all. If the single lane road is deemed adequate for the busiest times, why get rid of the cycle lane during the evenings and weekends when less cars means they wont need the other lane??? What if you fancied cycling into town with your family at the weekend? Madness.

I believe (but would have to check this again) that you actually get higher motor traffic flows into Central London after the evening peak than in the morning peak, as you get the theatre crowd etc., often driving in (and many use taxis, minicabs, and appcabs*, of course). I remember being in W1 at 4am on the 'Those London Lights' ride in late 2008 and it was unbelievably busy, on a Saturday night to be fair, but it felt as if it was still early evening. In the morning peak, non-public motor traffic flows into Central London are actually quite low, as the overwhelmingly vast majority of commuters arrive by public transport.

* This is a word they use in India, and I really like it.