Runners and Pace

I get what you mean, and I agree - I am so much faster than I used to be for the same amount of effort (and calories burned too, probably), however, I have days when it's easy and days when it's hard, even though I'm running at the same pace. The difference I can put down to tiredness, muscle fatigue, fuel and hormones. I love those rare days when I feel like I'm flying, but it doesn't happen a lot. Most of the time I have to work for it.

This is why most training is at an easy pace. Whatever you define easy as....

I find my pace increasing but I intentionally am working to get back to where I was. Things like hill training and interval training will naturally increase your base pace on flat.
Also I find when I am fighting the elements (rain/wind/snow) i push harder unconsciously and it leads to better splits.

This is normal. A prominent running coach, Jack Daniels, developed a pace system that has paces from slowest to fastest of E (easy), MP (marathon pace), T (tempo or threshold), I (interval), and R (repeat). Each is used for different purposes in training. Most running is done at E. MP has little physiological benefit, but you train at it to become accustomed to holding that pace for a marathon. T is lactic threshold; running at T builds endurance. I is faster than T, roughly equivalent to 5K race pace. Training at I is designed to increase your lactic threshold, i.e. make all your paces faster. R is roughly equivalent to the fastest you can run one mile. Training repeats at R is designed to force the runner into good running economy, improving form and running efficiency.

The thing is, these paces are *different* for different runners, and change over time and with training for an individual runner. But after you've trained with this system for a while, you learn to recognize easy or T level of effort regardless of what the actual measured pace is.

So yes, over time your paces can get faster; but you don't feel like you're flying at an easy pace, even if easy is now 10:00 per mile and it used to be 12:00 per mile. You feel like you're flying when you run a faster pace, maybe T, maybe you don't feel like you're flying until you run at R. But of course, you can't keep R up for long distances . . . whatever the measured pace of your R is.

Although about cycling, Greg LeMond said "It never gets easier, you just go faster".

When I started running I could comfortably sustain 11 minute miles, 10:00/mi felt like tempo and I could maybe run 9:00 pace for a 5k and felt like I was going to die at the end. I would feel like I was plodding along at 12:00/mi

Now I run more like 7:00 pace for easy miles, 6:30 for tempo, and I run 5ks at 5:30/mi. Plodding pace for me now is 8:00/mi.

However I *feel* the same now as I did back then. The 5:30/mi 5k today feels just as hard at my 9:00/mi 5k years ago.

I don't feel like I am flying along when I am running my 7:00/mi easy pace.

The same here. I remember when 12 or 13 minute miles were a struggle for me. Now, I consistently run 9:30 miles and some days I they feel like a struggle. Lately I've been hitting the high 8s and I definitely accuse my app of lying to me.

If you train at a similar pace, over time you will find your heart rate decreasing. As an example, I have been running the exact same 5km route over the last year and have seen my average heart rate drop from 90% to 75%. Certainly seems easier if not faster. That is progress for me.

I've never felt like a natural runner either. I have a very short stride and efforts to change that all end badly. Now, when someone criticizes my running form, I ask if they'd like to join me on my long run Sundays (which are 10+ miles). That usually quiets them pretty quick. Also, due a childhood injury, breathing through my nose is very difficult. Yep, I'm a mouth breather too. I will never be one of those graceful, pretty runners, but I get there and I improve. You will too.