Am not a fan of fish pie but even I fancied that. Made me want a potato ricer too.
I have a potato ricer, there is something very satisfying in pushing those spuds through the holes, far better than a masher, and no lumps. I have a very strong urge to buy a Mary Berry cook book now.
I've got a potato ricer and I love it. For mashed potato, I don't boil potatoes in water, I always cook them in their skins in the microwave, then either skin them before putting them through the ricer,or cut them in half put them in the ricer (cut side down) and the skin is left in the ricer so I scrape it out and give it to my dogs and put the rest of the potatoes through it.
I beat in hot milk and butter with a wooden spoon and the texture is lovely and creamy and so much better for the potatoes having been microwaved, not boiled....
Here endeth my mashed potato lesson!!!