In my view, quite a few major manufacturers are less than ethical with how they communicate with customers about rain jacket failure, particularly with DWRs, so it’s important to understand what a DWR is and isn’t supposed to do. I say this as a former warranty guy for a major manufacturer. This has nothing specifically to do with Montane.
DWR vs Membrane
A DWR is the water repellant coating on the outside of a jacket (“durable water repellant”). It is not the membrane, which is underneath the outer nylon fabric. Why bother with a DWR if the membrane will stop the rain anyways? Because if the outer nylon gets saturated then the air outside the membrane is fully saturated so breathability drops to zero. So a functional DWR is needed to achieve the breathable part of waterproof/breathable, not the waterproof part. A DWR is not the main line of defence against water intrusion.
What Failure Looks Like
When the DWR “fails” then water starts soaking into the outer nylon, which is easy to spot as “wetting out”.  Many people see this “wetting out” and jump to the incorrect conclusion that their membrane has failed, which is wrong, so I understand why telling customers to reapply DWR has become a knee-jerk reaction, but it’s still an inappropriate response if rain is really coming right through. DWR failure should not result in rain soaking through the jacket because the membrane should still be there to stop it.
If rain is coming right through the jacket, both the DWR and membrane aren’t doing their job. The challenge here is being sure rain is coming through, as opposed to accumulating water from condensation, sweat or soaking in through neck/wrist openings. The easiest way to tell the difference is that membrane failure typically happens in a defined area (e.g. around the shoulders) whereas with sweat and condensation you end up damp all over. Also once membrane failure gets really bad, then the water ingress is so rapid and substantial that it’s obviously not sweat or condensation. Once my Montane Minimus pants had 20+ days on them, I could put them on and in less than 30 seconds of walking through heavily dew covered grass my inside hiking pants would be drenched. Obviously not sweat or condensation.
How Manufacturers Mislead Customers
If you go into a store or contact a manufacturer and tell them your rain jacket is leaking, the first thing they’ll tell you to do is re-apply the DWR. I understand why dispensing this advice started – because a lot of customers see the face fabric (nylon) wetting out and incorrectly conclude the jacket is leaking when the membrane is still holding the rain at bay – but over the last 5 years or so this advice has become rampantly misused. It is being dispensed to people who are claiming real water penetration, which is a trick, because if your rain jacket is really leaking from membrane failure but you re-apply DWR, then the DWR will temporarily cover up for the failed membrane. Thus, the vendor can claim no issue, or more often, the customer really thinks the problem is solved and won’t notice it’s reoccurrence for a while – perhaps a couple more years if they use their gear rarely like most – at which point they don’t care about the jacket anymore and the vendor gets off. The simple truth is that if water is coming right through your jacket, then the membrane is not working. Whether or not the DWR is functional is a mute point.
I was in a Patagonia store recently asking about the warranty on their H2NO because I was considering an M10, and the sales guy was trying to convince me that warranty was irrelevant because water intrusion only indicates a need to reapply the DWR, and the customer is responsible for that. Per his explanation, there was no possible scenario where the membrane was at fault. The implication of this is that the DWR is everything and the membrane isn’t doing anything, which of course isn’t true. They’re basically trying to mislead the customer by placing all the onus on the DWR so the membrane goes unscrutinized. I actually  quite like Patagonia and saw this more as an example of a less than ethical and poorly educated salesperson.
Manufacturers have been so successful with their campaign to advocate for DWR reapplication to cover membrane failure that is now widely dispensed advice even within the outdoor community.
When to Re-Apply DWR
DWR should only be re-applied if your face fabric is wetting out, but the jacket itself is not leaking. Re-applying DWR here will restore breathability, which is the main responsibility DWR has. It also keeps the jacket lighter in your pack if the face fabric stays unsaturated. If your jacket is leaking right through, and it’s definitely not sweat or condensation, then the membrane is to blame, so correctly claim a warranty issue and don’t be mislead into re-applying DWR
Conclusions
All of what I’ve just said is general to the outdoor industry and not targeted at Montane in any way. I actually didn’t try to warranty any of my Minimus stuff because soon after it started leaking pretty bad the membrane started bubbling off heavily, so I figured they’d just say it was beyond it’s useful life even though it was pretty new.
Membranes in general don’t do well under strain, such as from shoulder straps of a heavy pack. Even heavy weight membranes eventually fail here. I’d like to see manufacturers use a non-breathable, more durable solution in high strain areas like the shoulders. Not heavier nylon which is used but does little, but rather replace the PU membrane with a more durable form of water protection – perhaps silicon coated fabric. Use the PU stuff for the rest of the jacket.
