A Comparison Trap - Comparing Myself to a Romanticized Past

Last week I went mountain biking for the first time since my ACL surgery. It was a mix of experiences - on one hand, it felt great to be back on a bike doing something I love. On the other hand, it felt a little demoralizing to feel like a beginner again; my turns weren't fluid, and I didn't trust my body (for good reason!) or my bike. It brings us back to the oft-quoted Theodore Roosevelt pearl: Comparison is the thief of joy.

But this is a sneaky comparison, because it seems reasonable - after all, aren't I comparing my performance to my past performance? Isn't that reasonable? Well, yes and no. Let's dive in:

1. I may be romanticizing that past memory. Did things really feel as natural and fluid on a bike as I remember? Maybe. Then again, maybe not. It certainly seems possible that I am conjuring nostalgia for a past that was never quite as rosy as I'm painting it to be now.
2. But let's say that's not the case and I'm not simply being nostalgic - maybe I really am remembering an accurate version of myself. Even if this is the case, comparison still has issues because I am probably comparing myself to a previous peak rather than a typical pre-injury day. I'm not comparing like-for-like; I'm comparing old me's peak performance to current me's first day back on the bike in nine months. 
3. The only accurate comparison would be to compare current-day me to the last time I was off the bike for nine months and had a major reconstructive surgery... which... doesn't exist. So there is no accurate comparison that I can reasonably make.
4. And, lastly, even if there was an accurate comparison I could make to my past performance, I would be wise to ask myself what I have to gain by comparing my experience to a past memory. Does it serve me? Because before I started comparing, I was enjoying the experience for what it was. And after I let comparison creep in, I felt discontent rather than enjoyment.

Comparison, even to some memory of our past selves, is a natural response, but it may not be a healthy response. Comparison to how I (think I) used to feel threatened to steal my joy in my first dirt ride in many months, and offered nothing positive in exchange for that enjoyment.

Where does comparison to a past imagined version of yourself threaten to steal your joy? Could you stay anchored in the pleasure of that moment rather than bowing to the internal pressure to compare? Which option leaves you feeling more fulfilled? What serves you better, being grounded in the moment or comparing the moment to a "better" past?