AFAIK there is now no requirement to wait for the gear to be down before selecting the next stage of flaps.
If you think about it, a couple of tonnes of gear going
down should not put strain on the pumps because it'll lower itself perfectly well! There are probably 'snubbers' in the hydraulic lines (or the gear itself) to prevent it coming down too quickly. In this situation a more likely scenario would be cavitation due to excess fluid flow.
Any Engineers out there shed more light on this?