I rode today seeking out chipseal to try out. I was riding my existing tires at 80F/85R as a very conservative test (highly confident that this will not be creating issues). I will be trying lower pressure later. And I mostly just paid attention to what I was feeling.
1) This is incrementally more comfortable than the low 90's pressures that I had been using.
2) There is a difference between the vibration of chipseal and a bumpy road. This is hardly a surprise, but I had never thought about that. They are pretty different issues, probably having different solutions (it seemed to me).
3) I paid really attention to the transition between good asphalt and the chipseal stuff as in "what is it about this chipseal that is uncomfortable?". And my conclusion was that vibration clearly coming up through the seatpost (as is mostly from the rear wheel) was probably 60% of the discomfort. I was not expecting that. So lower pressures and probably wider rear tires is definitely in play here.
There are other options including other tire pressures (and tire makes/models), latex tubes, and adding some kind of foam cushioning to my handlebars in the "sweet spot" a smidge to the rear of the horns of my shifters where my hands tend to spend most of their time. I am speculating that this will be the same as or more effective than either bar tape or a second glove.
This reminds me of the process that I have gone through more than once of trying to find 'a better sound from my guitar strings' (nylon - I play a classical guitar). But in the guitar case new strings cost (typically) between $7 and $20 and an aggressive 'start to end of string' is only 3-4 weeks. The experiment is a bit more expensive on a bike and the 'natural cycle' a good bit slower.
dave