Combine Sigmadrive and PU flexible coupler

[seaexplorer]

I am installing a new Molabo 50kW 48v electric inboard on my aluminium catamaran on the existing shaft.
It is replacing a diesel on the starboard side.

The old diesel had a standard Polyurethane Flexible Coupler between the transmission and the shaft.
This allows about 0.5 of a degree misalignment and also electrically isolates the stainless steel (+0.9v) shaft from the rest of the aluminium (-0.75v) hull which is a good thing.

I wanted something that would accomodate greater misalignment and be self adjusting so I bought a Sigmadrive Coupler with allows 3 degrees misaligment in all 3 directions.

Problem is, it is not electrically isolating.

I was thinking that I should just install both inline so that i get the benefits of both.

I am able to mount the engine further back to accomodate the extra shaft length created.

Can anyone think of why I shouldn't do this?