Stiff jeans

Tumbling would help and they will stretch back!!
Or wash with fabric softener??

Let them dry then just give them a five min tumble, I do this with lots of things.

Tumble 5 minutes, then dry on the line, then tumble 10 minutes.

If they are still not soft enough pan soak in very hot water, then wash as usual.

We like hot water to remove a bit of the "new colour".

Oh dear, kitty nothing worse than a DH feeling stiff and uncomfortable in the trouser department!

couldn't agree more *Phoenix "

Shake the jeans whilst wet and then lay them out on the work surface & give them a good flat handed bashing smoothing by them out at same time (iyswim).
Maybe a job for DH!

Phoenix - behave! We are both too old for that sort of nonsense!!

OK, what about trying twisting while wet?

Get him to hang on to the waist, grab the bottom of the legs, then twist them round and round (corkscrew fashion) then unwrap and twist the other way.

Should sort of "break" the fibres and soften them.

(Usual numpty disclaimer applies)

I'd still go for the tumble, on low, when nearly dry.

Many things that aren't meant to be tumble dried, I finish them off on low without difficulty.

Phoenix, I have a vision of your DH, doing the twist while wet.