I understand where you are coming from but my planes are not museum pieces. After all, normally we have to de-rust, de-burr, flatten, refinish, and do all manner of other things (including filing the mouths on some occasions) to our old planes before we can put them to use. Stanley made them by the millions and they are still readily available. Frog adjustment alone is not enough to allow the use of these blades on some planes. Slightly modifying a couple (out of the couple of hundred in the pile) just a tad didn’t seem such an issue, The amount of filing necessary is just enough to pass the shaving in a smoother and is small enough that the mouth still closes up with simple frog adjustment for a standard blade.
There has been a lot of buzz about the thicker blades being offered on the market and I had quite a bit of experience with thicker blades from my wooden planes, some of my non-Stanley transitional planes, some of my new planes, and one thick aftermarket blade from a different source, so I thought I would give these a try. I have extra original blades and new original thickness aftermarket blades, so getting a blade really wasn’t the issue. These blades were simply being mentioned as an alternative to the much more expensive, thicker, aftermarket blades being offered. Instructions for those will often mention the high probability that the mouths of the old planes may need to be modified.
The thicker blades add heft, resist chatter, make it easier for registration during freehand sharpening, and the modern steels seem be ever so slightly better than the original blades. Original blades will do the work well enough but I do like the thicker blades.
By all means, if you have a museum piece then don’t modify it.