I think that Sahib may have been referring to the U.S. MGN system.
There is still a wire neutral that will be carrying most of the current as long as it is intact.
In practice, most bad results occur in the immediate vicinity of substations. Some POCOs seem to have a problem understanding how to correct or mitigate those problems.
POCOs know little about how grounding works or at least what they want to admit about it. The MGN system was developed as a cheap method of increasing distribution capacity while reusing equipment. Often most distribution systems were 3 wire 2.4kv or 4.8kv Delta in 50s and earlier. Eventually pocos decided to add a 4th neutral wire and ground it repeatedly so it could be treated as a bare wire. The system could be raised to 4160 volts or 8300 volts in the case of 4.8 delta and the same transformers could be reused by connecting them phase to neutral. Capacity could be about doubled and voltage drop reduced by reusing the same equipment. And because the MGN has so many redundant water pipes and ground rods lightning related damages were reduced, especially on then fragile already decade old transformers. The practice continued as the insulation cost of transformers dropped and pocos decided to build new higher voltage lines or turn existing sub transmission lines into distribution lines. With 12 22 and 34 kv sub transmission lines a MGN was added, and single bushing 7200, 13200, and 19900 volt wound single bushing transformers could be used. Same went for brand new lines and the cost of an MGN was seen justifiable as compared to the extra cost from double busing transformers and extra cutouts. And if no MGN was run at all lightning arrestors away from the substation would have to be sized for a phase to phase voltage since a grounded down phase may cause a voltage rise before a breaker or fuse clears the fault.
It was a good idea back then when load was light, balanced and non harmonic rich. Today with the capacity of lines being pushed to the limit and with deteriorating equipment everywhere the disadvantages of the MGN is making itself known. This is something no poco wants to admit whos having a problem with stray voltage/current.
One major draw back of the MGN that I have seen (and I have personally seen this well more than once) is that downed conductors go unnoticed. Because the MGN and the ground are a return path for electrical loads, distribution breakers and re closers cant be set with low ground fault pick up values. That means a breaker or recloser GFI logic cant be set to trip the line at say 5 amps but rather hundreds of amps often 2/3 of the phase value. Often that means a downed conductor has to draw close to 600 to 800amps for some time for a trip to take place.
I had a phase come down further down the road a few years back from a fallen tree branch during an ice storm. The wire burned for litterally 2 and a half hours leaving a huge pothole in the street. Wasn't until poco got there and manually tripped the re closer to stop it. Same scenario plays out frequently when a pole comes down without hitting the MGN, especially on lower voltage systems.
I have read in a number of sources that about 1/3 of the primary grounded conductor current on our MGN system flows via the earth.
Usually its about half and half, but it can vary depending on the size of the neutral, load balance, harmonics, soil resistance, water pipe grounding, ect. It can be as low s 10% or as high as 90%.