80" is VERY long (that is our XL). I think 90" is excessive IMO. Some people like really long straps, but in my experience, most people do fine with 65-70". An average size person can do the twist (with rucksack straps) at that length. My dh is a size large and he can twist 65" straps.
People in Europe are often used to wrapping (well, more so than people here in the states) and so they like their MT straps very long (they prefer the XL over our standard straps). If you are a wrapper, and are used to dealing with long lengths of fabric, you won't think twice about, and will probably love the super long (scandi length) MT straps. If you are not used to that, you may like them shorter (I have had people complain that 60" straps were too long and cumbersome for them).
But Lilymama is right, it is definitely much easier to make them shorter than longer. I would plan to make them the length of the pattern (though no longer, your dh shouldn't need longer) and then keep in mind that you may want to make them shorter after y'all try it out. You can just cut the end to length, turn the raw edges under and topstitch. Takes no time at all.
HTH,
Kelley
Sahm to Xian (9) Piper (7) Arah (5) Ever (2) and Thrace (5.26.09)
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