N Recursions: The spectacle experiment: Why spectacles are likely to be bad for the eyes

Disclaimer: These are my personal observations. This is not medical advice.

You start noticing the various body positions that put maximum weight on your foot, only when your foot is injured and the pain keeps reminding you to be careful.

Same way, I started noticing a lot of tiny details about eye strain which people normally ignore or aren't able to notice. My eye strain became so severe that twelve ophthalmologists in two cities were not even able to diagnose the problem because they never encountered such a case.
These are what I learnt about fatigue related eye strain:

The root cause is a lack of 7 to 8 hours of uninterrupted sleep.
Plastic spectacle lenses strained my eyes faster than glass lenses. Even the top three world-class plastic lenses were nowhere close to the visual acuity provided by an ordinary glass lens that had no extra coatings.
Anti-reflective coatings did not help me. Aspherical lenses do not help. Eye exercises did not help (when muscles are tired, you should rest; not exercise them more). Eating carrots does not help (it's muscle strain; not a vitamin deficiency). Astigmatism lenses did not help (because I didn't have astigmatism). Dry eye remedies did not help (I didn't have dry eyes). Washing the eyes did not help. Looking at far-away objects did not help. Whole body exercise did not help. Eye drops did help a little, but it was only to give initial relief. Eye drops won't cure the problem and aren't meant to be used forever. The only thing that helped was getting 7 to 8 hours of uninterrupted sleep, taking rest periodically and having a well-balanced diet of properly cooked food.

With insufficient sleep, strain builds up and manifests as headaches, burning feeling in the front of the eyeballs, sharp stabbing pains behind the eyeballs, at the sides of the eye balls, muscles all around the eye feeling sore and at the most chronic stages, even the cheek muscles and muscles near the eyebrows feel strained and sore. Muscles around the eye also start twitching sometimes. When any of these happen, immediately stop straining your eyes and keep your eyes closed until the strain subsides, while also relaxing your face muscles and neck muscles. Do not aggravate the problem by trying to be a hero and straining your eyes even more. No career, job, boss or money is worth more than health.

Losing sleep is a silly thing to do.

A little experiment I tried
The blue shapes in the image below, are spectacle lenses viewed from the top, and this is about trying to read some words with the right eye. The left eye is closed or covered with one hand. When the lens was perpendicular to the words, the words were clear. But when the head was turned even slightly (not even as much as shown in the image), the word got distorted a bit. With some plastic lenses it's a blur. With some, it's a slight distortion. With glass lenses, it's far lesser. This blurring/distortion didn't happen when not wearing spectacles.

Something the industry does not seem to have considered is that our vision from both eyes is not always parallel.

I am 100% sure of the difference between glass and plastic lenses because I've got repeatable results during a three year period of checking. Scientists would of course call this a subjective result (and I agree), so I hope there would be someone who could verify it objectively. Sadly, the industry doesn't seem to have developed methods to measure extraocular muscle strain.

Keeping eyes fixed in one direction tires your muscles. That's a given. But I have a strong belief (this needs to be impartially and objectively verified) that the distortion created by spectacle lenses are the other major unexplored cause for eye strain and headaches. I don't know if wearing contact lenses would help (didn't try them because of the risk, and lasik doesn't work out for certain people. There is this study and this study that say contact lenses are less problematic than spectacles), but my opinion is that at least when working at a computer, it helps to wear spectacles with a glass lens instead of plastic lenses (it has to be on a frame that gives the same focal point position in front of your eye as the earlier spectacles, to avoid strain from eye accommodation). Keeping a diary/spreadsheet helps record how much uninterrupted sleep one has got everyday versus how bad the eye strain was when wearing spectacles with glass lenses versus plastic lenses. After not wearing spectacles and getting deep sleep, many nights, for two months, my eyesight actually improved.

Plastic lenses obviously have a safety benefit, but for me that's a lot less important than being able to avoid the horrible eye strain. For just sitting in front of the computer, I don't see any safety problems when using glass lenses.

This person Ben, also speaks of why glass lenses are better than plastic or polycarbonate.