Your have to compare with valverde, not with contador, Thomas is a complete rider as Valverde (number 1 cycling of the work). they can win in the cobbles (Valverde didnt try, but he has the potential and he did a good cobblestone stage), in hilly clasics, to be good in sprints, to be the best in climbs as Bretagne, to be good in ITT, to shine in GT, etc...) They are that kind of riders... people as well thought agan could be that way, I dont know, but obviously he has to lose weight for that.
Thomas came from the tracks as most of british riders and Valverde came from mountain races, that is what we has in Spain in juniors an amateurs...
The difference is that valverde improve withn hot and Thomas with rain...
anyway, Thomas is far of what valverde has got in cycling.
All this year he has been climbing as the best level. Algarve, Niza, Dauphiné...
In the past just in 2011 he was quite good in the clinmbs, he was working and he finished around 30, and he finished queen stage 25, helping Uran that got sick that day. He was at 7 minutes of Andy, but just 3 minutes of contador in that hard stage.
Anyway now, in his best age to perform, he is much better climber.
It is interesting to read this interview after Algarve.
http://www.cyclingquotes.com/news/geraint_thomas_good_for_the_confidence/
he some years train for the track and forget climbing, but when he train for mountains, he get good progress.
Evans was that kind of rider that can perform in very different scenes as well, but he came form Mountain Bike, no for the track, and he prefered Ardennes as cobbles.
Riders that have the potential to clim very well but he started in the track get his best in the mountain late in his career, if we consider 28 years (now 29) as late, becouse is not very late.
I think anyway the only country with that kind of riders is GB, maybe australia as well, but not everybody started in the track. Maybe 1 of 10 riders that start in the track in countries with traidtion, has potential to climb, but anyway, you have to develop it and it supossed to lose weight and train diferent. I am not an expert in that, but of course they are profesional, and for sure SKy will have, becouse thay have money to help in that; nuritionists, phisiologists, trainers,...
Today he was as his pace, so it is not the same that attacks and stop, but he was one of the best of the stage, he didnt work a lot, becouse was Porte there before, but he finished with the same time of the best...
We will see, in TdS he showed as the end that he cant be with the best climbers. and the Tour is long, i have serious doubts he can finish in the top 5, but today he was a big problem for Movistar. He worked little time, but very important work.