Well, I've concluded that my Irish Moss is mostly dead! It is pictured between the Blue Mouse Ears Hosta and the Cardinal Flower rosettes, in the narrow planting borders against the kennel and the house, and there is only one small patch that came back this year! In spite of the numerous pathway design flaws that will be reconciled, I felt it necessary to include photos (I have no pride!

lol! don't judge me!) to show the environment in which the Irish Moss was thriving for three years.
I designed and built this entire pathway to solve a problem with rain runoff from a very low pitch shed roof above, and to redirect the main roof downspout underground, away from the neighbor's drive, and to our back yard. I won't bore you all with the details of the entire design, but essentially, I installed a french drain / dry-well drainage system under the entire length of the pathway, and it passed the test from numerous 20 minute torrential downpours without a problem throughout the months of May and June of 2015! The narrow planting borders between the house and kennel are also designed with good drainage under quality loamy soil that drains well, while holding just the right amount of moisture for plant material to survive.
The Irish moss was planted three years ago, and it was thriving quite well, even through the downpours, and it grew beautifully to spill over the edging up to late winter of 2016. Typically, it would brown out a little in the Winter until new Spring growth appears, but it completely died off sometime before this Spring of 2016, and I'm very perplexed!
I prefer to use ground cover in the pathway planting borders to keep mulch out of the gravel pathway surface....daggone critters! So does anyone have suggestions on very low replacement ground cover for an area that receives only two hours of hot afternoon sun? I would like to use Elfin Thyme, but I don't think that it will get enough sun to survive........