Exposing my own ignorance here. I've seen a lot of comments about the design of this stage and others. Why should this not be a queen stage? And why do people now not like MTFs? It seems like when there are few, people clamor for more. When we get them, people say they create boring racing. Recognizing that these might be different folks. But honest questions, who has a moment to succinctly articulate basic stage design principles?
The thing about a really long, super difficult MTF is that it tends to negate any racing earlier in the stage unless sheer desperation necessitates it. The good news with regards to the Col de la Loze is that this is clearly a mountain which is hard enough that it will create gaps wherever they put it because the difficulty of those final few kilometres on top of already climbing for half an hour before you get there mean that it becomes impossible for it not to weed riders out who are suffering or struggling. However, the problem is that because that final climb is so difficult, there would be almost no chance of anybody making a move on an earlier climb - and here we had the Col de la Madeleine, one of France's greatest and toughest passes, from one of its toughest sides, too.
That in and of itself is fine, and we got some decent action for the last few kilometres here. But the issue comes when you start chaining mountain stages together. A finish like the Col de la Loze will work best as the first climb in a series of mountain stages, because if you put it later on in the chain of stages, it will neuter racing on earlier stages because nobody will dare go hard on the stages beforehand, because they could pay for it with minutes on the Col de la Loze. If Loze follows at the end of a group of mountain stages, you could then have a really well designed mountain stage with five passes and a descent finish, or a smaller MTF after a bigger climb, where the hardest climbing is 50km from home, but nobody will move until the last few hundred metres because they don't want to empty the tank before such a monolithic climb. However, do those stages in the opposite order, you will get the same amount of action on Col de la Loze, but you will get
far more action on the subsequent stage, because not only have the GC guys now got time gaps they have to work with, but the domestiques will be more tired from having had to work pace up the Col de la Loze, and so an attack from two or three climbs away from home is more likely to work, or an ambush plan like Heras to Pajares or Contador to Fuente Dé is easier to arrange because the leaders' teams' domestiques will find it harder to control who gets in to the break.
The 2009 Vuelta is a great example of this principle, where because of the steep final 8km of La Pandera and the kind of time that could be lost on it, the péloton soft-pedalled the far superior Velefique stage with 2x Velefique and Calar Alto, and also minimised the action on the Sierra Nevada (via Monachíl and Collado de las Sabinas) stage letting the break take both. A year later, a much better trifecta was planned, with Peña Cabarga being short but opening up small gaps because of how steep it was, incentivising some more action on Lagos de Covadonga, whose shape encourages attacking further out plus its status as an icon of the race infers prestige on it, and then the multi-col stage came at the end of the three mountain stages block (and had an MTF, at Coto Bello), and saw Fränk Schleck attack on the penultimate climb, a Euskaltel TTT to put Mikel Nieve up to the front, and more GC action than would have been the case had it had Lagos de Covadonga, a bona fide ESP-category MTF, the next day.
The Giro also shows us that the later you put a climb like Zoncolan, the less its effect. We have seen a couple of extremely underwhelming ascents of monolithic and iconic mountains in recent memory - 2009 Mont Ventoux in the Tour, and 2014 Giro Zoncolan being particularly clear, but 2011 Finestre is also a worthwhile one to mention. In all of these races the race lead was already on the shoulders of the strongest climber, Ventoux and Zoncolan stages are effectively Unipuerto whatever you do because of how steep they are, and so there was little action because nobody believed they could depose the leader - and they were probably right. In 2010 and 2011, however, Zoncolan was used on the penultimate weekend, and because of how difficult the mountain is, it automatically set up time gaps that needed to be dealt with in the following week, and improved later racing as a result. People like Arroyo and Joaquím Rodríguez were attacking 3 climbs and 65km from home in the Rifugio Gardeccia stage. This isolated nearly every team leader and created one of the most epic stages of the last 20 years. Without Zoncolan the previous day, that never happens; too many other teams' domestiques are strong enough to help their man, and so attacking on Giau is futile, the racing has to wait at least until Fedaia (Fedaia!!!!!). If you then put a Zoncolan MTF the following day, you postpone racing even longer, because people will understandably be concerned about going into the red and then facing a mountain as fearsome as the Zoncolan the following day.
It is therefore best to put the 'queen stage' after - preferably immediately after - a stage that forces the GC big guns to work hard - and preferably their helpers too. The most obvious examples of such stages are ITTs and tough MTFs. The Tour doesn't really have anything in its repertoire to fulfil this role in the same kind of way as Angliru or Zoncolan, but it does have some climbs which are long enough and sustained enough at a steep enough gradient that they would be able to be decisive enough even if Unipuerto. The Mont Ventoux is the archetype and the most famous of these, but there are options. The Col de la Loze is definitely one of these. Others off the top of my head are the Col du Grand-Colombier via Selle Fremontel, La Plagne, Col de Granon, Chamrousse via Luitel, Tourmalet, Galibier North and Madeleine South. You can throw Plateau de Beille and Alpe d'Huez in there too for the same reason as I mentioned Lagos de Covadonga earlier - their prestige at that difficulty level. These are climbs that don't need to be in the queen stage, and in fact with the possible exception of Alpe d'Huez (as that can be chained immediately off the back of bigger and stronger climbs like Croix de Fer and Galibier North) are perfectly fine to use as MTFs, but should not be in queen stages for that purpose (where possible, though, using them as passes or descent finishes in queen stages where possible is totally fine and should probably actually be encouraged, however).
Hope that makes sense, it's a bit thrown together.