The longest sentence ever pronounced at the fastest ever speed? (10)

'the longest sentence ever pronounced' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'at the fastest ever speed?' is the wordplay.
'at' says to put letters next to each other.
'the fastest ever' becomes 'record'.
'speed?' becomes 'time' (I can't justify this - if you can you should give a lot more credence to this answer).
'record' put next to 'time' is 'RECORDTIME'.

Can you help me to learn more?