The main point of the testing centred on Leffe Tripel: I tend to blithely deride the Leffe range as being ersatz factory-made versions of proper Belgian beer, but does that stand up to scrutiny? Obviously a genuine Trappist had to go in the mix for contrast, and I chose Westmalle Tripel, which I believe to be my favourite. From the abbey beers I took Bosteels Tripel Karmaliet -- an old reliable -- and Maredsous Tripel by big boys Duvel-Mortgaat, one I'd liked on the only previous occasion I'd tasted it. Finally I needed a wild card, a tripel I'd never had before and knew nothing about. This quest was answered by Tripel Horse, extra wild card points for being not Belgian, but from the River Horse brewery in New Jersey.

The first thing to say is that, although the beers were discernably different, they were all recognisably tripels: all had the powerful boozy heat (ABVs ranged from 8 to 10), the heavy sugary body and the spicy Belgian complexity. It was the minor differences in these elements that set them apart.
My least favourite was far and away the palest in colour with much more fizz than the others. The nose was incredibly sweet with an artificial syrup thing going on. It tasted heavily of cheap ginger ale and was drinkable but not very enjoyable over all. Amazingly, this turned out to be Tripel Karmaliet. Mrs Beer Nut liked it for its subtle floral notes and ranked it second; the best I can say is that I later got used to it. None went to waste.
Second-last was the haziest, with the biggest head of foam. It was the sweetest of the lot, reeking of dark sugar and with a big banana flavour among the spices, something I consider a flaw in the Belgian-style ales I've made myself. There's a certain balance to it, but mostly it tastes like tripel-by-numbers, made without the attentions of a caring brewer. No surprise here that it turned out to be Leffe Tripel.
Right in the middle there was another fairly heavy-going one, the darkest in colour with very little head or sparkle. Not so much spice or fruit here, just lots of heat and a hint of marker pens. Tripel isn't supposed to be an easy drinking style, so most of this can be forgiven, leaving a serious and heady sipper. This was the wife's favourite: Maredsous Tripel.
Which leaves the Trappist and the American vying for the top spot. Knock me down with a feather if Westmalle Tripel didn't come second. The aroma of this was gorgeous: subtle perfume, masking any hot sugary booze smells. The spices are to the fore on tasting: there's a hoppy bite at the front which is a little harsh, but then fades to allow lavender and cloves through. Beautiful, but not as nice as...
... Tripel Horse. Another powerhouse like the Maredsous at 10% ABV, but doesn't really show signs of all that alcohol. Instead it has zest: a zingy aroma followed by lemons and mandarins on the palate for an invigorating refreshing effect, enhanced by a vigorous sparkle. The finish is sweet and sugary, but not in an unpleasant cloying way -- sweet and lip-smacking instead. Would I have credited it as an American take on a Belgian style? Never in a million beers.
And then there was the unpleasant business of disposing of the guts of five bottles of tripel. It's hard work this blind tasting lark, but rewarding nonetheless.