Hey,
Lots of misinformation here. First up, the PowerSuppliesAustralia page is not nonsensical, it's correct. For most of the standard Meanwell LED CC Drivers (as with other brands), they should not be naively put in parallel. Different CC supplies (and CV likewise, or CCCV) have different feedback regulation topologies, and they handle parallel operation differently. Some of them can work in practice, some of them cannot, but non of them will guarantee output regulation. The only exception is for drivers with specifically designed current sharing hooks, either via a separate control line, or by more sophisticated output sensing.
In addition, PSA is correct that there is a general belief that isolating the supplies via a diode (this is known as an ORing diode) allows parallel operation. That is indeed false. As pointed out by Enderman, the diode allows for redundant operation where if one driver fails, the rest can take over safely. Note that this is in the context of a typical 'N+1' power supply set-up (i.e. one extra power supply is required), which is tolerant for 1 failure without system overload, and also requires the drivers to be parallel-capable. The diode (oftentimes an 'ideal diode' is used (FET) for lower losses, otherwise don't use a regular diode, just a schottky) also prevents fault current from flowing back to the defective supply. Besides dis-regulation occurring due to feedback messing up, it's also typical for drivers to have different output impedances, which will really mess with the load sharing.
Now in practice, depending on the topology of the feedback regulation (which we do not know unless the manufacturer specifically calls it out or provides a datasheet), it can be possible to have CC drivers in parallel, but care needs to be taken to make sure the connecting leads and wire have as close a symmetry as possible, and likewise with the leads converging at the load as close as possible. The supplies also need to be placed in the same environment since imbalanced heating will have an effect on symmetry in a larger way than you expect. ORing diodes together with the power leads typically also add some real-world resistance, which will also help in some sort of power balancing. Clearly then, adding series resistors to each supply will help significantly in current sharing, but at the cost of inefficiency.
There are some supplies which are both CV and CC, and those can be configured for parallel operation with a 'master' set at CV and the rest in CC, but this places limitations on the load, and is difficult to change on the fly (as in Barkuti's application). The non-linearity of LEDs as a load also makes the situation a little more complex.
Barkuti, based on what you are describing, and if you like the Meanwell LED drivers, why not just get a single one of their B-type LED driver capable of driving the entire load? You can then easily throttle down the current using swtiches and resistors across the DIM+ DIM- lines. Then you get guaranteed CC operation, not worry about driver disregulation, and it's likely cheaper and easier to set up too.
