Reading through threads on "sevice intervals" and "when to service" etc, I find it interesting that it seems to be mostly instructors tell people that regular service intervals aren't important.
Being a regulator technician, i found that when our instructors did bring in regs they were in terrible shape. So much so that we had to institute a new policy stating that they would no longer get the staff rate (free labor, discounted parts) if the reg wasnt brought in at least annually.
It isn't just instructors, it is also those who think they know a lot about regs, but really don't know all that much. Before I became a technician I used to go long periods between servicing - this is when I lived in the tropics and dived a lot. The technicians always griped because of the condition of the reg when it was serviced. The reality was, it should have been serviced once or twice per year rather than the recommended interval of two years. With all that being stated, I have noticed many divers will believe the DM/Instructors in the tropics simply because they have the title - don't always believe them.
Please describe “terrible shape”
Lots of mineral build up on the inside and outside of the first and second stages, o-rings that have dried up making it difficult to remove, sand on the inside that rub holes in a diaphragm and then the owner gripes because they have to pay for a new one, seashells in the second stage, ignored frayed hoses that are covered up by the hose protector, creeping IP/MP or poor inhalation effort, shredded o-ring in the first stage (yes I've seen that happen), and the list goes on. Build of corrosion is the big one.
I think this is also a testament to how robust most modern regulators are. They still work fine even when the internals are in a state that a tech might describe as "terrible".
Yes, they are, however, don't let that be an excuse to not service or to encourage others that regs can go a long periods between servicing. The performance of the reg does diminish when not serviced. Normally people don't notice the lack of performance as time goes along since it is a slow process. When I went long periods between servicing I never noticed, but when I used it after servicing I could tell a significant difference.
Whenever a person tells me regs can go longer than the recommend interval I simply ask them how much longer in terms of time and number of dives. None of those people have been able to give an answer. The manufactures have given a time line based off of past experience. The recommended interval isn't perfect, yes, you can go longer, but how much longer and how does one, who is not knowladgeble and experienced with regulators (i.e. most recreational divers), know when it has gone long enough?