Oh dear!
Just like specialist fire alarm and fire extinguisher firms have to cope with competition from multi discipline FM firms with engineers who are air con/cctv/plumbing/PAT/EICR/EL/Alarm/extinguisher/fire door engineers rolled into one a lot of fire risk assessors are primarily H&S or Env. Health consultants who have to be multi-disciplined (sometimes adding water hygiene, asbestos & CDM) due to economic pressures of the market (end customers don't always want the hassle of two separate site visits and certainly not the extra proportionate cost).
It can work (we do it) but it requires good ongoing training, CPD and support and also a good skills matrix to ensure they don't get allocated to work out of their depth. We retain specialist fire safety only staff for the more complex work, plus BAFE make sure we are ensuring we are keeping things shipshape.
I have seen some howlers in FRAs by all sorts of providers such as extinguisher firms, H&S consultancies and employment law consultancies and some quite good stuff done in house by RP's staff, the latter proving the original intent of the law that you don't always have to use an external third party, nor be accredited, to produce a suitable assessment.