He wanted you to slow down in a hurry,well at 7 miles speed 176 ,flaps 10 wint do much to you.
Eventhough gear may me a tad too early,it wont hurt too much either,you wre fully configured around 1500 ft..
Maybe it is his comfort zone or maybe there is something we dont know.
Flaps 10 as mentionned is great to help in increasing a tad your descent rate or not allowing speed increase on the glide with winds changing into a tailwind but sometimes the gear is the easiest option.
You will have plenty of time to practice those idle thrust to 500 ft when the time comes,your capt was maybe tired or junior,in anycase you can prove yourself later.
I have let a few fos who insisted to practice idle thrust to the limit perform a go around because at the end they put the gear a tad too late..a good eye opener for fuel saving record..