Speed chess isn't BG. In BG we often need to move 2 pieces and sometimes 4 and not counting moving the hit checker(s) to the bar. I played many thousands of speed chess games in my youth and don't recall making an illegal move more than a few times.
Why are illegal moves so much more common in BG? Some of this I think stems from moving more than 1 piece/turn, but I think another cause is all the look alike pieces clustered together. Another cause, is that as I think you're pointing out, the BG community (at least in the US) hasn't properly addressed penalties for illegal moves.
Why am I apologizing publically? Well in the diagram below, I recall you had 6 seconds on the clock and I think I had 28 seconds. I rolled 55 and as I was playing 8/2(2)(!!) you, wanting to make sure there was no conflict started saying." Woe Woe Woe" and I realized OMFG, told you I was sorry, and since I didn't want you to lose on time by this possible distraction, reminded you that you have only 6 seconds left on the clock. I then played what I had to play 7/2(2) 6/1x(2).
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| XGID=-a-BBCBBB----Ab--cbbbbA-a-:0:0:1:55:8:7:1:9:10 | |||||
| Blue to play 55 | |||||
| 1. | 4-ply | 7/2(2) 6/1*(2) | eq: +0.2602 | |||
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eXtreme Gammon Version: 2.10, MET: Kazaross XG2
This brings up interesting rules questions. Lets say we enforce a rule that says that bcuz I made an illegal play, I have to let my 12 sec. delay time run out and then move. However, I haven't fully made an illegal move until I've hit my clock. Then you could say "illegal" and stop the clock.
We had a match recorder who was also a monitor so there'd be no argument. It is also possible for the monitor to say illegal and certainly one of us would center the clock prior to 12 sec delay taking away and causing loss of what was left of our reserve times.
But what if someone less scrupulous has just a few seconds left and incorrectly screams, "illegal" and stops the clock, gaining a precious few seconds to think about the cube, count pips or to think about how to play a few of his possible rolls?
Food for thought?
As I apologize for my sloppiness I will also point out that Bob was a perfect gentleman gamesman while in severe time pressure. There was no fast grabbing or non shaking of dice and his hand wasn't resting on the clock when closed out like I've seen some do.
OTB no one timed out and I managed to roll well enough later to hop the 5 prime and win after some action.