Doug...!
The problem with your idea of cooking vegetables separately is that....
I would require 8, (or more), separate saucepans in which to cook my 8, (or more), different vegetables, each day....
And I don't have that many saucepans....or gas rings to put them on.... to comply with that idea!
So...I use two saucepans...One for the boiled potatoes....and one for the remainder of the vegetables, all together....Sorted!
...(and "steaming" stuff is for posh people; folks who like semi-cooked, crunchy vegetables.... and Vegetarians)....

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So...the layout on the dinner plate is: Meat, Potatoes, and Vegetables. All lubricated with a heavenly helping of my special gravy sauce, which contains all sorts of extra magic ingredients to titivate the palate!
The water, saved from the vegetables, is used to make the gravy, so it contains lots of goodness.
In other words.....Its a typical
English Dinner!...Like Mum used to make in the olden days!...

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An "English Dinner" is like an "England Breakfast"...probably unique to England!
Paul....Dining Tonight...

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Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.