[GWBullshit]

Appreciate the reply and advice.

Having said that I've had this model for quite a while now and have been doing this since I can remember and never had this issue until the latest macOS update, which from what I've researched seems to be affecting loads of people with all sorts of newer, much fancier processors than what I have.

While I will definitely keep your advice in mind going forward, it seems that this issue sprung up only after this last update, which is strange because I remember reading something about "improved energy management" or some such.