Puc, The short answer is 'Yes'.
The sidestand is strong enough to carry the weight of the bike. I had a tire starting to show cord while cruising across South Dakota several years ago (last time I will ever run a D404 - it was only about 4000 miles old). Found a local Honda dealer in Chamberlain, SD that had a E3 in stock. Pulled into their shop and the technician asked if I had tools to help (I wanted to get it done in a hurry and he was elbow deep in another job). Yes, I did.
Took the saddle bags off, removed the throttle side muffler, loosened the brake caliper bracket, loosened the axle pinch bolt, and removed the axle nut from the clutch side. This was done while on the side stand.
The technician came over and put a floor jack under the foot board clamp and jacked it up with most of the weight being carried by the sidestand. I had never seen this done. We pulled the axle and removed the tire. While he was changing out the tire, I asked where his Honda Moly60 was so I could lube the drive splines (pointed to his workbench).
Overall, I was back on the road in under 30 minutes (and about $300 lighter in the wallet if I recall correctly). Paid the tech a $20 tip for his help and for letting me help so it could be done faster.
So, yes, the sidestand can hold the weight (sample test size of 1).
RR