His side had to overcome their poorest performance of the nine-tournament series yesterday when failing to qualify for the Cup quarter-finals after losing to Fiji and dark horses Spain. Wales picked themselves up this afternoon to pick up the silverware with a 27-5 victory over Scotland in the Bowl final.
Earlier Wales had to withstand a spirited display by Portugal just to make the final. The rapidly improving Portuguese were on the cusp of a shock semi-final victory but Dan Fish touched down in the dying seconds to give Rhys Jones the chance to snatch victory. His conversion saw Wales sneak into the final with a hard fought and gutsy 28-26 win.
"I'm just pleased we got something out of it today because we had a poor day yesterday by our standards," admitted John.
"It was probably the worst day we've had all season - we haven't lost two games in a pool all year and that was really disappointing but they responded the way we would have wanted to.
"To win all three games today - albeit with a bit of struggle in the first two - the boys came through that mental challenge but we're still frustrated after yesterday because we lost our position in the series as we were seventh but now finish eighth because Argentina have done so well."
Argentina's haul of 15 points from Twickenham, where they made the Third Place final, saw them edge one point ahead of Wales who picked up eight points from the London event.
Despite picking up the Bowl, John couldn't hide his disappointment after his side failed to go through to the main draw after picking up just one win on day one against Zimbabwe.
"Going into the tournament we felt we had an opportunity to get through to the quarter finals but we gave Spain 17 points yesterday and that was disappointing - they are a good side and you can't give anyone 17 points so they deserved their win but the biggest thing is we responded as a squad today and managed to get something out of it."
Looking back on an eventual campaign which began on Australia's Gold Coast last November, John said there were a number of positives to take out of the nine-tournament series.
"We made seven quarter-finals this year and out of those we could have won four of them - the pleasing thing for me is when we have lost a quarter-final we have battled on and got to a Plate final three times so that is a step up from last year.
"We've got 91 points this year, we only had 62 last year and last year was more than we had ever scored before so it's more progression but we have got to try and get up as high as we can. The boys have done really well this year, but it wouldn't take a lot more to do a lot better either."