Interestingly, Ken Young at ARRS is opposed to accepting enroute times for records, ie. 25 km enroute to marathon. He explained to me once why and I was not convinced by his reasons which were mostly about proper documentation, having timers at the correct enroute spot, etc. With chip mats these days, his concerns could be addressed easily. If he insists on 3 stopped times on every runner eligible for a record, we have problems. Chip mats won't yield 3 times.
There's also the point that a runner has to complete the entire race distance for any enroute records to count.
Then we also run into the drop & separation issue for records...1 meter per kilometer of running for drop (25m in a 25 km) & 30% of the race distance for separation (7.5 km in a 25 km).
I'm a big fan of Ken's work (his data base is extraordinary) but we differ on the issue of enroute records.