As already stated by many, Yes, it's perfectly acceptable. Provided it's been applied correctly: In my years as a procedural Approach controller I'd use it "usually" in the following situations.

Two departures, en-route on the same track, slap them both with a ROC restriction, then the number 2 can depart when the first is through a couple of thousand feet. Saves having to wait for the 10/20 miles whichever is applicable. The can then get further unrestricted climb with the neighbouring (radar equipped) sector.

The second scenario is when two acft are on diverging tracks, let's say by 30degrees (off VOR), you can apply ROC until the first has reached the required 10nm. Saves a bit of time...

This is of course a highly simplified explaination and all assosciated laws/logic needs to be taken into account...:ok:

With my previous pure proc exp of about 6 years( without radar in TMA ) in quite busy traffic vertical rate restricted climb & descent is a very useful tool which can be easily applied to three acft simultaniously ( or more if you are experienced enough).
This is an exellent tool to reduce your rt load( report level,etc.) & give attention to other conflicts & traffic.

I come to this thread late but I used the technique only once to climb a BUA 1-11 under a Dan Air Comet.
I started with 2000ft vertical as they left Edinburgh and let the climb rate do the rest up to FL250 IIRC.
That's going back to the 1970s.

A perfectly good procedure!

Explain....?

PS Just answered my own question - can now visualise the scenario, not to mention the performance in getting the pilots to understand the required ROCs!

The answer is ...
 

The question is "Is it acceptable under ICAO 4444 to use rates of climb/descent for separation in a non radar environment?" The answer is a qualified yes. It all depends on the air traffic environment (e.g. route structure etc) and the circumstances (e.g. aircraft types involved; weather etc). The most common use is to specify rates of climb so that vertical sep. is maintained between two aircraft and this is normally done between two successive departures.

Procedural approach control was quite common in the UK back in the 1960s and I was fortunate to do my training at Edinburgh (1964-65) when there was no alternative! It really made you learn the basics of being a controller!