Link11 on hf is for los or near los only, not distant over the horizon like typical hf comms, wich is odd because they also have a uhf version of the protocol. I think they cover a cbg with it and that's all they want from it. The link sig might be strong enough for those within los to be unaware if the other signal.
Thus the jammers dilemma, how to jam the jam resistant.
Link-11 is more designed for regional use, beyond LOS but not really long range. That is why you find it on the frequencies you do, most typically below 15 MHz with a real emphasis below 10 MHz. It is often used it at beyond LOS, but seldom as far as 600+ miles. At ranges where you could use the ground wave portion of a 2 to 6 MHz signal. And yes, you can do Link-11 on VHF and UHF also, but that really is LOS.
Link-11 is for the entire battle group, whatever kind of group it is, and anyone attached to it. Or it can be simply two (or more) ships independent steaming but supporting each other. Push the pickets out to screening positions 75+ miles away and the battle group commander, or anyone else in the network, can see the radar / sonar / ESM picture from the pickets. You can put up the Lamps 3 bird and push it out 200 miles (or more, but then he starts getting short on fuel), and watch his LN-66 picture. Better yet, when prosecuting an ESM contact you can put the -3 out on a tangential bearing to get another ESM bearing cut on the target, giving you a position plot. Since the link to the aircraft (this is a dedicated link, not Link-11) is on a tight beam and at UHF the chances of it being intercepted or giving your position away are lessened, so you can end up with a 2D location of a threat while not exposing yourself by lighting up any radars, and often at ranges beyond what your radar could see anyway. That 2D position then goes out over Link-11 to the rest of the units. And of course if it is a carrier battle group you can put up an E-2 Hawkeye and push him out several hundred miles with all the same advantages.
You can have the entire group in EMCON, using only passive systems, and one platform active and providing the tactical picture to everyone, obscuring details of who is in your group or where, exactly, you are (assuming you push the active platform outside the group). This works particularly well with a helo or fixed wing aircraft as the active emitter. Of course, your Link transmission gives you a way, but it is of limited use as many potential bad guys can't get as much information on an HF signal as VHF and up.
T!