Well if you have 3 engines ....
It's not a problem,
AW101 can achieve its best range speed with one engine deliberately shutdown, the MGB is designed for it ('declutch' the engine before shutdown) and the aircraft tested to allow for recovery time from OEI to TEI in the case of a running engine also failing. Normal SOPs for some operators as it does increase the range a useful amount
I can see issues with going deliberate OEI on a twin though, you would have to have a bl00dy reliable way of restarting the off engine when in autorotation and I guess a minimum AGL to allow the engine to restart and to be able to recover the aircraft to level flight. The mention of a high pressure syetym is fine provided it allows you to have more than 1 shot at it!, probably any weight increase for that system would negate the range benefit
I suspect there would be issues with flying in icing conditions or in moisture with an engine off as well
DM