In general the summer Main Line routes are busy
I would recommend you make reservations for the majority of journeys
Some passenger flows are expected to be busier than normally, especially for specific events, and before and after each days events
East Coast already have arrangements in place for events that end late, which could impact northbound passenger loadings (and expect similar issues with other such services out of London)
Consequently this may push some passengers to use the northbound sleeper instead
On the plus side, it is a First Class ALR, so providing you make the reservations at least three weeks in advance there should not be any issue with the sleepers and the majority of Main Line services, although your preferred seat may not be available
I shall be dong my best to avoid the railways altogether when the Olympics are on
I have to agree with you on this one, for the Main Line services
It is for this reason I am not completing an ALR this year (as I prefer the period June to July), as many people have changed their holiday plans and travelling before or after the Olympics