Roger, if it was a contractors' style saw, that would indeed have the table connected to the trunnion. While that makes for more difficult alignment maintenance, it potentially makes for more stable alignment if the tool is moved around as would be the case with a "contractor" moving job sites. (The little, portable saws we have today were not so prevalent a long time ago) With the guts fastened to the table, if you bump the table, (or the short cabinet below) the table and the "guts" are still one unit. (if you drop it out of the back of a truck, all bets are off, however.... ) Cabinet saws are much easier to do the alignment since the table is independent of the "guts" and in general, cabinet saws don't do much traveling.
That, by the way, is "my" theory and may very well be hog-wash.
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The most expensive tool is the one you buy "cheaply" and often...