Yes sure we can

With the shoe on the counter, slide the heel down the side off the edge of the counter, 5, 10, 15mm. To help show the customer what will happen to the toe.

• It goes up.
• Also the area where the ball of the foot contacts the ground may move.

Still not sure? Get the customer to put both shoes on and then stand with just the front half sole area, ball of the foot on 5,10,15mm of eva or pad etc, to help the customer get a feel for whats going to work
As a general guide a soft floppy shoe will be Ok to lower lots, like up to 50mm in some cases! Where as a stiff patent platform won't be so good. but generally you can always take 5-10mm off.
1 Get agreement with customer - mark back of left
2 Remove old heel
3 Grind lower - check angle
4 Put new heel on