To put Andy finishing 17 minutes back today into perspective with past years...
In 2011 in Andalucia he finished 23 minutes back on stage 2 (also race a couple tropheo's this year, but finished back there in each).
In 2010 in TA, he finished 8:30 back in stage 3, then 7 back the next stage, and 20 back in Chieti.
In 2009 in Cali, he did well to finish 10th the 2nd stage, 3rd stage though he finished 16 minutes back.
So in conclusion, finishing back there in his first race of the season is nothing new for Andy. And as we can see by his overall performances in those 3 years, finishing minutes back in his first race can potentially have very little affect on his overall year. Now of course, this year is slightly different to those years with him having been fighting to come back from a couple bad years. But his goals remain the same and the point stands that this performance is in-line with his first performances in some of his best years. starting the year slowly is how Andy does things, I don't think it a big necessity for him to be up there competing for the win for him to be good in the Ardennes and Tour. His form of build up to his targets isn't the same as the Froome or Contador approach of winning or placing high in all their first races, he follows a gradual build up to his goals.
So for that reason, I don't think there is much point in reading a ton into his result today. If he fall back into the dnf pattern he had in early 2013 and 2012 then I'll start to worry. But as of now, there isn't much reason to be too concerned.