I think you may have answered your own question, Juddz. If you're going to put in storage for a long time there's going to be some "drying out", but in the long run the effect on engine life will be negligible. That being said, most manufacturers assume that the vehicle will be driven at least once a month in normal use. So what you might do is this:

• Leave the battery in the car and connected to a battery tender 24/7. It won't hurt the battery. Trust me.
• Once a month (I use the 1st Saturday), go out to the shed and fire your baby up. Let it run until it reaches normal operating temperature, meaning the cooling fan cycles on and off twice. Note: This is important because you need to get the oil hot enough to burn off any water that may have condensed in the engine!
• While the engine's warming up, cycle the steering lock to lock, pump the brakes, roll the windows up and down, open and close all the doors, raise & lower the top, and stand on each door sill and bounce up and down a few times to get some action in the shocks.

Things fall in to disrepair and fail because they don't get used. Fluids go stale, seals dry out, etc... So get out there and spend some quality time with your baby even during the winter months. Your car will love you back 10x over because when springtime comes around you'll know its ready to go. And if you find yourself with that unexpected warm, salt-free March day all you have to do is disconnect the battery tender and head out!