In this photo I have placed a marine grade adhesive lined heat shrink connector into the jaws of my Klein "dimple" / staking crimper. It certainly does not take a rocket scientist to understand why a dimple crimper should be avoided for use on an insulated terminal. Once you squeeze the grip the dimple can puncture the expensive terminals protective heat shrink thus rendering the protection you paid for virtually pointless.
Note: This Klein crimper shows a spot for insulated crimps and also says insulated & non-insulated for the dimple crimp slots. I can not, with a good conscience, recommend anyone using this particular crimper, or any crimper like this, on any heat shrink insulated termination.
Using inexpensive, one size fits all, crimp tools will probably not save you any money in the long run. If and when you do use a dimple/staking crimper the dimple should be made opposite the seam, always "saddle the seam" this means face the seam AWAY from the dimpler, not at it as I have shown.
In this photo I am showing the orientation many folks often use, it is incorrect. Doing this can split the brazed seam and cause the termination to fail at a very low pull out strain. If you must use a dimple type crimper the dimple should be be opposite the seam.
Perhaps the most lacking feature of a dimple or staking crimper is that you lose any sort of strain relief crimping on standard insulated crimps. The entire load is taken by just the crimp barrel.
A double crimp ratcheting tool is designed to make two crimps, one for strain relief, which has different sized dies, and one for the bare wire crimp. If you are trying to wire a boat to be ABYC compliant, which by the way is not a requirement for a DIY, a dimple or staking crimper would not qualify as the correct tool to use under E-11 for insulated terminals.