I don’t have direct experience with the OTPS, but regardless I can’t recommend using a device outside its specification. If it’s rated to max 66.8A then its usage should be kept within that. If you want to push that boundary you’ll need to contact Outland to discuss, but I expect if it was capable of reliably being used outside the rating then it would just have a higher rating.
“Boosting” would require some form of hybrid power, where there’s some amount of power stored on the ROV to supplement the tether power.
You could potentially add a bank of capacitors to act as a short term battery during brief load spikes, but an “extra push” while diving would be an extended load (not a momentary spike), and would likely need a power supply mixer that uses the tether supply for the base load, and allows an onboard battery to handle the extra load during extended peaks.
We’ve worked on something similar previously, but haven’t yet finished development/validation of it, and it’s not being actively worked on at the moment.