Mo Farah insists his challenge for next year's Virgin London Marathon has been strengthened by his decision to race just half the distance today.
The double Olympic gold medallist, who won 5,000m and 10,000m gold at London 2012, had faced criticism for his decision to drop out after just 13 miles.
But he claims judgement should only be made after he makes his debut over the full distance in 2014.
"Next year I'll come and do the full marathon and I've learned the biggest lesson of my life," he said.
"If I had come here next year and made a mess of the race I don't think I could have dealt with that.
"The biggest challenge I had was picking up the right drink and I made a mess of that. I'll watch the race back to see how much of a mess I made of it."
Farah, 30, has yet to decide where his long-term ambitions lie in athletics. Although the marathon at the 2016 Olympics remains a possibility, the only aim for this season is defending his 5,000m world title in Moscow and upgrading the silver he won in Daegu two years ago over 10,000m.
"This year I'll be concentrating on the track. It's hard to do marathon and track racing," he added.
In the men's race, Ethiopian Tsegaye Kebede edged out 2011 champion Emmanuel Mutai in the closing stages for his second win in 2:06:04.
Derek Hawkins was the first British man home in 2:16.51, though he showed his annoyance at crossing the line because he was nearly three minutes outside his target time.
Susan Partridge produced a brilliant sprint finish down The Mall to win the domestic battle in the women's race, finishing just 15 seconds inside the two hour, 31 minute time required to make the British squad for this summer's IAAF World Championships.
Meanwhile, Kenya's Priscah Jeptoo took advantage of a dramatic fall by Olympic champion Tiki Gelana, who clashed with wheelchair racer Josh Cassidy, to claim line honours.
© Sportsbeat 2013