IO540,
There was actually nothing wrong with the planning. With a ground temperature of +20 C and tops forecast at around 10,000 there is very little space to get icing. Unless you find a little convective cell as I did.
There is nothing wrong with having a look as long as your OUTs are in order. Mine were, and I could still go up almost as quickly as I would have gone down, performance-wise.
It's still not the alternating change from VMC to IMC and back when flying IFR. It's the change TO IMC when you wanted to remain VMC that has a higher risk.