cost me around £150.

Books, from Amazon-UK range from a few pence to a few pounds. Downloading costs me nothing. The Kindle connects direct to Amazon.

To be truthful I didn't read all of your post, not comprehensively. I was unsure of the point you are making. All the figures and calculations seem a lot of intense hard work.

But forgive me for saying, how relevant is this? Doesn't the way we read boil down simply to personal choice? What I mean is, I've read books all my life, physical books I have purchased from book stores, or borrowed from libraries. I used to read 2,3, 4 books a week at some stages of my life. I now read books via a Kindle. My choice to do that and I didn't need to do any printing costs/calculations to arrive at the decision to use it.

I haven't been lied to, as far as I can gather.

You say YMMV, your mileage may vary or your results may vary, meaning, I guess, that you accept others will have different views and values. Doesn't this diminish your claim that we have been lied to? If I was to make such a bold claim, I surely would not end my thesis with a, "Of course, you may have different reasons or results or findings, and I accept that my own considerable calculations, findings, and conclusions may not apply to you. If so, then therefore please ignore my claim that you have been lied to".

Not good practice I feel.

Think of all the trees you are cutting down...

Mark