Irony?

Further to my post the other day, discussing the use of irony, in which I commented on an ironic message emblazoned in French on the chest of a young lady's t-shirt (it said "Speak slowly, I'm blonde"), today, I saw another lady, somewhat older, rather rounded, rolling her way gently through the Metro.

This lady was also wearing a t-shirt with a message on the chest, this time in English (which meant I didn't need to look so hard to read it). The message, in sparkly silver diamante, simply said: "I think slowly". I'm not sure whether any irony was intended or not.

Philosophically though, it raises an interesting question. Is it possible to think slowly? Presumably the speed at which thoughts flash through the brain is pretty much the same for everyone. Perhaps it would have been better to say: "I come to conclusions slowly". Yes, I'd buy a t-shirt like that.