Toughened glass eric? NOOOOOOO - that toughening has an effedct of making the glass ever so, ever so, ever so, ever so, ever so, ever so, ever so, ever so, SLIGHTLY bowed - therefore it's WRONG!
Wrong I tell you
sorry lol I'm feeling frisky this morning.
Mike - I have used diamond plates and scary sharp, right up to 7000 flour paper and my general verdict is ummm both
HTH!
No seriously - for regrinding damaged primary bevels or fettling a new average priced chisel, a diamond plate is the only way to go to keep your sanity - I recently bought a 140grit plate from axminster, which was a little spendy £70 ish, BUT having done the same job with paper over hours, and hours and hours, I can tell you the £70 is worth it and will last for decades.
I then use 300 / 600 / 1200 plates with the "ruler trick" and ONLY go past 1200 using paper to really polish the secondary if I'm doing finer work (which doesn't happen often) or chiselling pine as that needs the sharpest chisel you can get to reduce tearout with dovetails etc (plus utilising the "either side" technique) - otherwise for most general chiselling 1200 is enough as long as you use the ruler trick which makes a bigger difference to the edge than you might think.
David Charlesworth shows the "lift" method apparently used for centuries and centuries according to some, but with the modification of using a ruler (which has been populariased by, and thus attributed to him even if it's not strictly accurate) , which gives infinitely repeatable results, which the lift method does not - and has at least one YT on it, Rod Cosman also has a YT on it for cross reference, both of those two should be more than adequate to get you started and a keen enough edge providing you follow instructions correctly.
DMT diamond stones are argued to be the best, but seriously spendy, mine are Ultex which aree used by several members here and much cheaper but still good thick plates.
I also have some faithful cheapos for "sharpening" things like card scrapers, paint scraper blades and such like which is impossible with paper, as it just tears right through it.
HTH
(Edited for the pedants)
PS the ruler trick is only "supposed" to be used for plane blades, but will also work for chisels used for all work except paring and dovetailing, and probably even then because a microback bevel created by 3 swipes will be so small as to be almost invisible to the naked eye thus rasing the cutting edge of the chisel by less than the thickness of a human hair - which again for most work is more than adequate.