The gear pump is a constant volume flow pump and the fluid will obviously run where there is least resistance.
Hence you get the various uneven movements, and sometimes a lot of yaw (enough to make the ball go all the way to one side) temporarily.
I heard that Socata did an optional flow control kit at some stage, and a google on
landing gear flow restrictor
digs up loads of hits.
Do any GA retractables actually use this method?
I can see that artificially creating a flow restriction would create a constant-volume-rate flow into that part of the system, and would be very cheap.
They are around, but that is quite rare. Also placing in the system is critical as you would want to remain maximum flow (=speed) for the emergency gear operation.
Again, nearly all hydraulic gear aircraft will have this kind of behaviour. You might want to have a look at the gear cycling of a Cessna single engine aircraft, that gear looks really weird during cycling. Yet that is also normal operation on these.
The only aircraft I have ever flown that had perfectly synchronous gear movement were twin Cessnas with electrically (mechanically) operated landing gears that are driven by one common motor. Like the C340 and 421B. But this has absolutely no noticeable advantage over the seemingly random behavior of the hydraulic gears.
The Beech 33 also has synchronous gear because all components are linked mechanically. I just shiver at the thought to adjust this system in case of trouble. In the PA46 the main gear will also comes down on both sides pretty much the same time. The reason is that it will basically free fall and the hydraulic back pressure only increases on the last part before it gets locked. On the way up it is the same as the back pressure rises the higher the gear gets. But in the end I would not tune the gear system…
