Thanks for writing to us. The Matterhorn is a step up from the standard climbs of the Grand Teton and Mt Blanc. I’ve guided the Hornli ridge years ago but all the moderate routes have similar technical difficulties. I recall it being about 4000 feet from the Hornli hut to the summit. None of the climbing is technically very hard. It’s similar to the upper Exum or the Owens/Spalding on the Grand Teton in terms of absolute difficulty but MUCH longer and so more demanding. Its more akin to the East Ridge of the grand in terms of scale and difficulty.
Physical stamina (fueled by aerobic endurance) will be the main factor in determining success and how much fun you have. The more aerobically fit you are the better you’ll be able to handle the long day of moderate climbing.
The 8 week Basic mountaineering plan is not a short cut to fitness. We put it together at the request of several guide services who have clients show up with pretty much zero fitness. So…its called basic for a reason and should only be used by those with very little time to prepare. You and you husband will be much better served by the 16 week plan.
I hope this helps,