Deano 777
Is the problem at LCY that on approach engine power may need to be increased to provide adequate bleed air pressure to operate the wing de-icing but it is this extra power that causes difficulty in maintaining the steep glideslope ? And then the short runway at LCY (1319m LDA) is not the place to be arriving with an excess of energy.
Genuine question, I was never Q400 qualified, just basing it on experience of other types.