This is my opinion, and it is just that...we have one.
The older saws that I have which were from the era I like have very old and brittle steel, it's very easy to break a tooth when sharpening, and even if one is careful it can happen.
The plate is also thicker than more modern saws, but some had thinner plates back in the 1800s. I really haven't been around handsaws too much in several years, so my dates could be off here, but sometime around 1830 to 1850 you see saw plates that are stamped
GERMAN STEEL, and I like those also...but mostly what I am after is the nicer style handles as they feel good in my hand.
In another thread you posted, Pedder mentioned a handle that fits your hand well, and I think this is very important. This is kinda why Disston saws were so popular, IMO. The handsaws that Disston made in the early 1900s up to and in the 40s had mostly Apple wood handle with soft lines that felt good in the hand compared to some others. This is just my opinion, as I don't like Disston as the person he was, and I didn't even know him...but it's just principal in how he became the megalomaniac he became, in a similar way that Henry Ford did...yet another megalomaniac. I digress.
At some point in the 1950s the Disston empire was already crumbling...but this was an empire that had amassed more than 100 years prior and built up for 100 years, mostly after Henry himself had passed. Disston had some good techniques with using sandstone wheels to taper the blades, they turn slow but because of that they are relatively safe. Probably not a great idea to do that with a 3600 RPM bench grinder, just sayin'...
Also, we can't generalize on some of these points, because there are always exceptions. There were a limited number of what would be considered a dovetail saw. A smaller saw with a shorter blade, thinner plate, which was intended for finer joinery work such as furniture drawers, stuff like that...I only have a single example I paid about $150 for, more than I have paid for most saws, and it was kind of special though. The legendary Tom Law had refurbished it and it has bluing on the steel. Law used to like to do that I've been told by more than one person, and the person I bought it from had Law refurb other saws, but this was the only one he would sell. One of the few saws I have bought that was sharp enough to use, and it had a plastic blade guard on it that I was told Law put on it when he sent it back to the guy. The plate is not too thin, IMO, it's around .020" as I recall, and a Disston 70 has a more modern, better quality steel plate on it. Those are from the 20th century but just to point out that the older dovetail saws have steel that is also 150+ years old and we have learned a great deal about spring steel since, which all saws use, there are many variants, 1095 being just one.
You can use any saw for most all work, no matter how thick the plate is. More important is getting a saw that feels good to you, and preferably with sound steel that is not brittle and won't snap teeth getting it sharpened. There are so many good quality saws, I could only give you many ideas, but I would encourage you to have one made for you custom if you can find someone to work with your hand size and will make you something like you want and what wood you like...you will ultimately end up with a tool that will have special meaning to you. And if you can build your own saw, I recommend that. Hard to get parts, but if you were interested in doing that, I could give you some parts that you could do that with, I would need to dig around and see what I have in my pile of backs and plates that didn't work out for whatever reason. In some cases they were cut too short, stuff like that. I might even have a couple Johnny Kleso (Rexxmill) split-nuts, they work pretty good, but like all split-nuts once you take the handle off the saw, they most likely will not go back together without being detectable. All split-nuts exhibit this problem and why they were less than desirable to slotted screws like Disston used. Those are known as Chicago Screws, and the screw portion is blind. One problem is the amount they will adjust, but in general that was the advantage...I think the split-nuts just look the shizzle when sanded smooth, but as I mention all of them, even modern saws that use them, will loose that smoothness the first time you disassemble the handsaw to fix a plate or other. If you use a folded back you will almost always need to remove the handle and readjust the back, so I prefer slotted. But those folded back work just fine. I don't by into any metal holds any tension unless it's forced to do something it doesn't want, metal doesn't move like wood with climate, it does some, but not nearly as much. If you read something about "tensioning a blade by wacking it with a ball peen, it's a good time to consider if this is fact or not. I do believe you can change/fix a plate by peening on an anvil, just that I don't go along with having to re-tension the steel. That seems like phooey to me...but judge for yourself, there are others that believe this and even on this forum, so I'll leave it at that and say if you call it tensioning it's ok, just that I won't call it that as I don't believe steel hold tension. Even if you bend spring steel, it's pretty much bent for good...
And lastly, if you have any saws now and don't know how to sharpen them, learn to do that before you think about getting anymore saws. You must learn how to sharpen if you plan to use handsaws in the future. If not, look for other tools to do the same tasks.
Probably way more than you wanted to hear about the saw plate, but there are many factors to consider for each of us and we all have different needs.
EDIT: those 1830-1850ish saws said
"GERMAN STEEL" not made in Germany. That is the type of thing that will bring the haters out on the Internet. LOL
