It's better to cut the stump as low as possible unles you make a seat out of it.....Cheers mate, i work in that industry for local government and we're always trialling things with problem trees that the arborist crew remove such as chinese tallow and camphor laurels that sucker everywhere once they've been stump ground. Hadn't heard of that stuff, did some last week leaving the stumps at about waist height and drilling holes in with slow release glyphosate capsules to see if that stops them coming back.
After that stuff is applied you should be able to level it of pretty soon that stuff is more powerful than glyphosate are which is mainly a translocated herbicide acting on leaves pumpinig it down through the Xylem, and Phloem plant cells -
stump remover does the job better imo its horses for courses - drill holes as you know and pour it in many times let it soak in deep it will work leaving the stump high is making it harder imo cut it as low as you can - we used to use a mattic pick to remove the exces soil an surface roots the use that stuff a far neater job, plus it will rot the stump...