I find it way better at that point when the ground speed mini is enourmous to leave it in, but DISCONNECT the auto throttles and hand fly the approach at a more reasonable speed (DO NOT SELECT THE MORE RESONABLE SPEED). Fly your aircraft and use the ground speed mini as a warning that you are going to need to increase power.
YOU can increase power way faster than the auto throttles can. and before you start whinging about it being unsafe, ALPHA FLOOR is still available and you will also get the "Speed Speed" warnings if you are projected to be too slow in a few seconds, again giving you the chance to push up the throttles. IF you have lost the ability to do both fly the airplne and the throttles, then leave the auto pilot hooked up and focus on the speed.
Ground speed mini is a nice idea, but the real reason it was created is that the auto throttles are too slow, and with the fixed throttles you have no ability to help them out.
Selecting a speed is definately a bad idea, so if ATC is forcing you slower than ground speed mini, u are just going to have to do it the old fashioned way.
Cheers
Wino