My oily skin has always been a bit temperamental (during pregnancy and after particularly). Recently (DD is 5m) whilst relatively clear, it has felt rather 'congested' and I tried not using moisturiser in the morning pre-make up (never used it at night anyway) and IT WORKED. Skin feels much better and is still clear.
... but I am worried that at 38 this month, I should be doing something more to prevent ageiing??? Should I be using an eye cream at the very least? I cleanse religiously morning and night ... but that is it at the moment.
I personally can't imagine going without moisturiser but there are a few skincare gurus like Eve Lom and Dr Hauschka who say that you should never use moisturiser at night, only a light moisturiser where you need it during the day.
If it's working for you, you should be ok. If you're worried about aging though you should make sure you use some kind of sun protection. There are loads you can get that are oil-free and lightweight. Maybe check out Clinique City Block? Sorry, I sound like a scary lady who works on a beauty counter don't I ? I promise you I'm not.