I'm going to be installing a switch and 40 workstations/printers in a building. All the rooms have raised floors with cable trays running in various grids and there are cable trays going between the rooms accessible from the basement. Most of the runs will be between 200' and 300'. All the runs will be going from the switch in the computer room, under the floor in cable trays and then popping up and directly connecting to the workstations/printers.
I remember back in the day it was a big deal to use solid cable for horizontal runs but that was usually between a switches or other stationary devices. I've been seeing problems with similar situations where a solid cable was used because people move stuff around and eventually the conductors break.
Now in the modern day does anyone see a problem with using stranded cables for this type of installation?
Use solid core wire for structured wiring (in-wall, above ceiling, etc), it's cheaper.
Use stranded core wire for everything else (eg, wall to computer, in-rack, patch panel to switch, etc)
To directly address the question as stated:
That makes no sense at all - whoever made this a big deal was uninformed at best.
As stated above, solid core is for structured wiring, not "stationary devices" which have a tendency of moving over time. It should only be used where the endpoints are part of the building.
Correct - which is why you never use solid core outside structured wiring.
You never cited any actual problems with using stranded core cabling in the first place. The main reason it wasn't used for structured wiring is price, stranded is more expensive than solid core. A minor secondary reason is that solid core is much easier to get a good connection in punchdown blocks and keystone jacks.
Note: There are different C8P8/RJ45 ends for Solid and Stranded wire. Be sure you use the correct end for the wire if you want a reliable connection. The pins when viewed cable end-on look straight for stranded wire, and look forked for solid wire. Diagram courtesy cableorganizer.com.