Tenor guitar in bluegrass?

I have been playing in a bluegrass jam lately that often has more mandolins than guitars, and one of the mandolin players often has to play guitar for the whole session.

I'd like to be able to fill in on guitar to give him a chance to play mandolin when there aren't any other guitar players, but I don't like guitar tuning.

So, my question is: would a tenor guitar played with a boom-chuck rhythm style like a regular guitar work in a bluegrass context? I'd tune it GDAE so I could still play breaks with the fingerings I know from mandolin.

Those fingerings are hard to translate directly on a 23” scale to support EADG tuning, as one finger generally covers two frets on a mandolin but only one on a guitar.

Tenor banjo players often use different fingerings and voicings for their chords than mandolin players because of the much longer fret scale.
Tenor guitars have the same scale lengths as tenor banjos.

Old tenor banjo tutorials are not hard to find, and many provide excellent voicings and fingerings for common chords. If you're going to tune GDAE, you'll have to transpose the chord names: i.e. a tenor banjo CGDA C major chord will be a G major chord if you tune GDAE.

As far as the use of tenor guitar in bluegrass music-- although I cannot think of an example of a well known bluegrass band that had a tenor guitar player, there were a couple of guys called The Delmore Brothers, and Rabon Delmore's instrument was the tenor guitar. Look 'em up.

I know I won't be able to do mandolin chop chords on a tenor guitar - I was going to use open chord voicings and let them ring out like a 6-string guitar. The fingerings i was going to use from mandolin were more for the melody, which I think I can do without as much issue although I may have to modify then a bit. I tend to use mostly frets 0-5 for most songs anyway. The only reason I don't want to learn entirely new fingerings is that this would be a second instrument for me and I'd like to keep focusing on getting better on mandolin as my primary.

I suppose the alternative would be to use an octave mandolin, but those don't seem to have as deep of bass as a guitar typically does, which is something I'm looking for.

Thanks for the reference on the use of tenor guitar in bluegrass, I'll check them out!

Barre chords are your friends playing tenor in a bluegrass or old time jam. Very easy to move up and down the neck and to get 7th and minor variations. Yes it will work. Plus you can flatpick the tune or break if you are so inclined.

A good C chord for tenor guitar in GDAE tuning [or octave mandolin]: 5-5-3-0. It gives a full triad with the root on the bottom.
A good A chord: 2-2-4-0. No bar needed. A minor: 2-2-3-0.
E: 4-2-2-4. E minor: 4-2-2-3. You'll have to use a small bar on these two.
The old 2 finger standard G, D, and D minor chords work really well as-is.

That should be enough to get you started.

If it is just a jam for fun I don't see why a tenor guitar wouldn't work, especially for rhythm. If it's a jam that really wants to sound like Bluegrass, you'll not be able to supply the bass notes of a dreadnought (the "boom" part of boom-chuck), and you certainly can't do a G-run (an essential part of true Bluegrass rhythm guitar) like a dreadnought.

In our jam a good guitar player started playing tenor (GDAE) and played both rhythm and good breaks on it. He traded it for a tenor banjo and now he brings that sometimes. It has worked fine. I myself have occasionally played my little Regal tenor in the jam although not on fast tunes. You won't get as impressive a boom-chuck but you can do it. I say, give it a try.