Bike fit, was never really convinced of the benefit, nto for me anyway, and where I end up in the reults table, just tweaked my road bike until I felt comfortable, and managed to achieve a position that got this, and could cycle all distances.
However, I decided to treat myself to a TT bike, and did a lot of research in what I wanted, geometry etc, and decided on a bike. However, the bike could only be brought through dealers who included a bike fit, so popped along, and tried the bike, and within seconds of being on it, was told I wasn't suited to the bike. I have 'runners' legs which are too long for the bike I was after (a Boardman TT), as it's too long for me. So we tried a few other bikes, and ended up getting a Kuota, which incidently was £150 less than the Boardman, and once on it, it felt instantly more comfortable.
The bike is currently being built, and I'm back in a couple of weeks for a 2 - 3 hour bike fit. At this time, all adjustments will be made in order to maximise comfort and power on the bike. Any changes tha are required are included, and could involve steb, bars, aero bars, cranks and cleats. At the end of it, I should have a bike that won't cause me any issues, other than fatigue, that should be comforatble, maximise my power (or lack of), and set up so I can run off of it as best I can.
Only time will tell if it's worth it, but investing a couple of grand in a bike, then the £90 for the fit (half price) seemed worthwhile.