Short answer to this is yes, it would still spike, but then all you would do is decrease your duty cycle.
Don't how the haltec does it but I assume it just controls a mac valve, so your tuner just needs to start the bleed off later if its just spiking as boost is ramping. It just makes it a bit less aggressive.
If you are using an external wastegate with both ports being used, an old school way is just crimp the vac line going to the top port with a hose clamp just enough to restrict flow, or put a bleed valve in that line and bleed it off. In both cases the top chamber will have less pressure and reduce your boost, and can be adjusted when ever you want without really messing up your ecu if its just setting fixed parameters to a mac valve's duty cycle and gain.