It is true that the shields recharge rate is very slow. Therefore, better use it for slowing down, or just increase it when not engaged and speed is not a factor.

I usually increase them at the beginning of the mission, if nothing much is happening and I'm in no hurry to engage. If there is no time for that, increase your laser recharge and shunt energy from cannons to shields. Former recharge much faster than the latter. This is also a great tactic when you are in a tight spot and need emergency power to shields.

I wouldn't do that if the target you are engaging is a slow moving one. In that case better recharge shields in maximum than reduce speed by cutting down your throttle.

I'm usually transferring energy this way when I need full shields fast and don't have the time to wait for outer layer to charge. Lasers recharge fast and you can use them even if they are still recharging. Of course, they're not supercharged for a minute or so, but still better then waiting for full shields if you are chasing some capital ship or attacking a station.

I do agree about reducing speed by transferring power to shields. I use that method extensively in dogfights against smaller and faster but lightly shielded starfighters like A-wings. Instead of slowing down to 2/3 or 1/3 throttle for tighter turns, you get the some thing by boosting shield power. You'll never outrun A-wings, but with better turn rate and full shields, you don't have to. You can even suffer a few hits attacking it head on because they will not withstand linked laser fire.

Depends,
If you are waiting around for some action to come your way or are just patrolling then I tend to set everything to maximum recharge and dump all of the laser energy into shields. In combat, I'll have Laser recharge at max and others at normal, then just dump laser energy in as and when needed

Like the others say, rather than using the throttle if you are tailing a slow ship, sometimes it is worth bumping both recharge rates to max to slow down, although don't forget;

Press ENTER to match speed
and you get a manoeuvring boost at 1/3rd throttle.

so maybe its worth using the throttle to control your speed.

It's slow, but it's the same rate you get when continuously dumping lasers into shields as well (while lasers re depleted). Dumping lasers into shields just SEEMS better because you're draining the laser batteries all at once. Of course, then you have to wait for your lasers to recharge.

Yeah, but you can fire lasers while they are recharging. Granted, they are not at full power but still... That's why it seems faster.