Any thoughts on the forum on tendon injury prevention? I found a great article on the topic while doing some research for a future blog post and I'd love to start a discussion on the topic here. Here's a link to the Practical Horseman article:
As an amateur show jumper and an owner of a horse that injured a deep digital flexor tendon a while back, I have a lot of interest towards this topic. I'm a person that has been taught early on by my trainers and instructors to always treat the legs after strenuous work be it a jumping lesson, flat lesson or a long hack. However I believe that caring for the legs is only one aspect of promoting healthy tendons. As Palm Beach stated, the conditioning program is equally or even more important than what you do to the legs after the ride. While it's hard to estimate which factor is more important, it's safe to say neither should be ignored. With carefully planned and executed conditioning, many health problems can be dodged even if less attention is paid to cooling and poulticing. However, poulticing will not help if the horse is constantly overworked and is warmed up poorly before the ride.
One cannot overlook the effects of obesity and poor hoof care, either. As mentioned in the article OP is referring to, most injuries of the tendons occur due to continuous build-up of microinjuries over time. Horses also get injured acutely from time to time so avoiding risks like jumping big jumps, lunging or free-lunging on a soft footing is always a good idea.
Then there's the aspect of supplements and liniments. In my opinion, those are mainly easy money makers for equestrian businesses and don't really help. While feeding them probably won't do any harm, I'd suggest investing more time, money and effort in things like making sure your footing is safe, you condition your horse according to it's physique, cool and poultice if necessary, make sure your horse's hooves are trimmed correctly and that he's not overweight.