Just wiped a whole reply - start again
Yes Maurice, it's the 6 saddles, adjustable for height and intonation that I mean - typically on a strat. The theory goes that a solid bridge (I've successfully used angle aluminium), screwed down well, will transfer string vibrations to the body better than anything with movable parts and/or small surface area in contact.
As to intonation; for sure, a solid bridge
has to be fixed in the right place viz-a-viz the fretboard. But if that is correct, the fretboard accurate and the strings sounding an in-tune chord at the nut, then a straight bar anywhere up the fretboard should sound the same in-tune intervals. Any variance introduced by string gauge should be less than that caused by bar pressure.
Regards, Tony.
(Explanation - read at your own risk)
The steel guitar is not a "just temperament" instrument. You can play a G# and make it sound different to an Ab. In terms of true pitch, G# is actually a higher note than Ab and many folk instruments reflect this (
that's why, for instance, Scottish bagpipes sound right playing a pentatonic scale in A, but some notes can sound way off in other keys as their notes are all based on the intervals of a true A scale). A lot of "standard" instruments, piano for example, only have the ability to sound one note to cover both of these tones. So they are tuned to a compromise, i.e. midway between, throughout the range (that's just temperament). Those strat style bridges "compensate" to allow two or more notes, when fingered at different frets, to sound in-tune; like the midway tuning on a piano.
Steel guitar, violin, most bagpipes etc. are tuned to unjust temperament - tuned to sound right in the natural (open strings) key of the instrument and no compromise is made. A C6th tuning is based on the open-string notes being bang on the intervals of a scale in C - nothing else. The advantage is that once you bar at the various positions up the fretboard, you have perfectly in-tune chords at every place else too, because you are doing the same thing as if re-tuning the "open" strings. That's why, mainly seen in pedal steel circles, you get tuning charts where you have different Hz numbers for each string and not 440 all the way. E.G. on E9th you tune the Es and Bs to 440 (they are a perfect 5th apart and fit with each other) but G#s, D etc. are tuned slightly flat to fit the "E based "unjust" scale.

Here's one I made earlier - the pickup is from a Jazz bass (rewound) and the "bridge" is covered by a cut-down Jazz-Bass pickup cover as a hand rest.