This enabled an additional 15-20 containers to be carried per train, giving a 20% productivity gain, and was partly enabled by Network Rail completing the lengthening of loops on the route northwards from Southampton via Banbury.
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a type of sound change when a sound (especially a vowel) lengthens
This enabled an additional 15-20 containers to be carried per train, giving a 20% productivity gain, and was partly enabled by Network Rail completing the lengthening of loops on the route northwards