Less is more? Often said and often miss quoted. I would like to put myself forward as a pretty standard hypocritical minimalist.
When packing for a trip I do try to take only what I need, which often requires me to think, pack, re think, re pack and then turn it on its head and start again, but the intention is to take as little as possible.
Apart from the obvious weight and organisation issues that come with too much equipment, there is the gradual (insert trust issues here) realisation that less is actually more.
1 camera, 2 lenses equal 2 choices. add another 2 lenses and you have 4 choices and probably another camera to save time. Add a flash, a tripod and even more lenses and filters and you have even more choices. The reality is, and I say this in all seriousness, a good image maker can probably get the job done with a randomly selected lens and any camera they are familiar enough with.
Photography that requires fast thinking and reactions are anathema to an over equipped photographer. Apart from the time taken to think through your options, there is the time needed to change camera or lenses to create the visualised image (that is still only in your head). Many images are fleeting in street, sport, reportage and candid portraiture. There is often not even time to zoom, just point the camera and shoot the composition that presents itself.
Studio and location shooters have the luxury of creative "hours", but often, even they keep it simple and they have assistants.
Present someone with too many options and they will get confused, lack focus and hesitate. Present them with one choice of tool, but complete freedom in how they use that tool and watch them come up with dozens of clever ways of using that single perspective creatively.
There are many other techniques that can speed up image capture (but all of them come to nothing if you are caught flat footed by indecision).
1) Leave a good gap between the "perspective" rendered by different lenses. One of the easiest ways to get caught up is to have lenses of slightly different focal lengths, but which render similar perspective to the subject. An 85mm lens and a 135mm lens have slightly different magnifications, but can produce images near enough to the same as to make choosing between them pointless. The 135mm may get you a little closer and the 85mm may include a bit more, but at the end of the day, the real difference is minor. I used to joke that my ideal canon kit was (in full frame values) a 24mm for landscapes, a 35mm for street, a 135mm for portraiture and a 400mm lens for sport and wildlife, but really, that is all I would need. I almost changed some of my olympus lenses for 4 "perfect" primes (Leica 12 and 42.5, Olympus 75 and 300) of effectively the same focal lengths just recently, but size/weight/cost and wife stopped me. Use lenses that give you a clearly wide, semi wide, natural and compressed perspective and avoid more than one in each category. Perspective is more important than magnification when choosing and using lenses lenses.
2) Use pre focussed lenses for street grab shots. That is, focus manually to about 2 metres and disengage the AF, set the aperture to about f5.6 with a wide or semi wide lens. This will allow for point and shoot without focussing. Set the ISO high enough to guarantee 1/125th or faster shutter speeds.
3) carry only as many lenses as you have hands/cameras. My standard method these days is to have a camera on a long strap hanging on my waist, with a 17mm lens pre focussed at about 5 feet at f4-8 and another camera held in my left hand with a longer lens at the ready. the second camera will be used at the eye, so it needs to be responsive, but the strap camera only needs to pointed in the right direction and the shutter fired. If you wish to carry more lenses, make sure to follow the rule above about being a genuine change in perspective, no "filler" focal lengths.
4) Use primes. This one is a matter of taste and to some extent existing habits. My old "light" kit was a 17-40 and 70-200 f4L Canon lens kit and one body (or a full and crop body combo to allow for slight the variation in lens focal lengths). These two lenses and the occasional addition of a fast prime, made me feel pretty bullet proof, but after years of using this or a similar combination, I realised that I often used only one or two focal lengths regularly and was frustrated when the lenses were set to something else and I was unprepared. The 70-200 was almost always on around 135mm or occasionally 200mm on a full frame (often wishing for more) and the 17-40 became a favourite on a crop body at about 17-20 (28-35mm equiv). My own preference for primes comes from being better at composing quickly with a pre determined focal length, rather than the mental "clutter" of composing by zooming, then shooting. If you trust yourself to pre set your focal length and leave it, then I guess you can have the best of both worlds.
5) Be organised. No lens caps or reversed hoods (I use screw in metal ones for rigidity and never take them off). Lenses on cameras, camera in hand or close to. Have your camera on any time you may come across an image (carry more batteries if you need to) and set your camera correctly for the likely image you will capture. It is better to have a larger camera bag, allowing for quick dumping of one camera or lens in an empty space and equally fast retrieval of a the next bit of gear and remember empty space weighs nothing. If shooting landscapes, put your polariser filter on the lens and leave it there.
6) Don't hesitate. More images gives you more to choose from, more practice and more chance of grabbing the fleeting nano second that can make all of the difference. Timing is still important, but if in doubt, shoot.
7) Only buy and use what you need, but get the best lens you can afford in that class. If you love wildlife photography, but never take landscapes, why buy a wide angle, when the money could get you a better long lens. Too many photographers starting out try to cover the full range of focal lengths, often with multiple overlaps. They will eventually whittle their kit down, but too late to avoid the clutter and cost of doing it the long way round (talking from experience here).
My own kit?
Street and travel. The "strap" body with the 17mm and the "hand" body with either the 45 or 75mm. Occasionally the 25mm instead of the 17mm. On long trips I may pack a shadow kit as replacements for lost or damaged gear.
Portrait work. One body (a spare in the bag if working) 25, 45 and 75mm (or 40-150 possibly from now on) just for coverage of smaller or larger groups. I always head toward the longer lens unless it is not possible.
Landscape. Pen F (electronic shutter) with the 12-40 and 40-150 pro lenses. These lenses break one of my cardinal rules of not needing fast zooms for slow work, but their edge to edge sharpness and weather proofing as well as the ability to frame tightly (relevant for the time rich landscape shooter) make them the best choices for an Olympus user.
Stage work. The 40-150 and occasional 75 for very low light. Occasionally the 75-300 that is surprisingly useful if the light is good and maybe a 25mm for whole stage shots.
So, less is more? Yes please. The clean, creative freedom of the uncluttered and organised image maker for me. Never again the bags of gear, packed safely but uselessly away, struggling in the hot sun and cursing my hobby.