I'd love to get it 100% original and put it on auto cycle, just to scare the folks at OSHA to death.
The lack of auto-cycle log splitters has nothing to do with OSHA... more to do with design, engineering, cost, reliability and the "lawyer factor". It just can't be done effectively and reliably with off-the-shelf hydraulic components. My splitter is 100% hands-free auto-cycle and still manufactured/marketed, but both the valve and cylinder are proprietary "in-house" designed, engineered and manufactured... the only thing off-the-shelf about it is the engine bolted to it. The valve is a simple single-spool/single lever and only contains a single o-ring that can be replaced using nothing but a couple monkey wrenches (actually the lever isn't part of the valve, it connects to the spool via the auto-cycle linkage). As far as I know, the government hasn't yet gotten around to regulating log splitters (I'm sure it's just a matter of time), just the engines powering them.
It ain't necessary for hydraulic log splitters to be the huge, bulky, heavy things that most are... that's just the "easiest", fastest and cheapest way to build them by bolting/welding off-the-shelf parts together without the need for any real engineering or fabricating skills. My splitter, that's been manufactured since the 70's, is proof of that! Fully hands-free auto cycle, auto-throttle, 25-inch stroke with under 10-second cycle time, stroke length is infinitely adjustable via a simple thumb screw, uses a floating push plate that grabs angle-cut rounds without slipping, the fluid reservoir is in the beam and has no vent, it does not use a pressure relief valve of any sort, it does not use Lovejoy couplings, has only one single small diameter hydraulic hose, it generates pressures around 8000 PSI so the cylinder can be very small diameter and light-weight yet provide a
true 18-tons of sustained splitting power throughout the full ram travel, stores in less area than a small lawn tractor...
and weighs less than 200-pounds full of fluids and dripping wet! I can lift the beam and roll it around using one finger!
OK... Back to the topic.
I split some by manual power, but only if it's a relatively small quantity of straight-grained, easy splitting stuff... if it won't "pop" with a single swing of the axe or maul I bring out the splitter, I work smarter, not harder. Exercise?? I get plenty of exercise doing other stuff... beating my body up swinging a striking tool against logs that fight back, even slightly, ain't worth it to me. Manual splitting may be good exercise for the muscles... but the repetitive motion and shock does more damage than good to joints, cartilage, tendons and whatnot.
addendum; Oh... and if my splitter wasn't so light and handy to use I'd probably do more with the axe/maul... but it's just so darn easy to grab and roll where I want it, right up next to the log being split. If I had to move rounds to the splitter, rather than the splitter to the rounds, I likely see it different.