String bet?

IMHO: Perfectly acceptable, albeit a little strange since it was essentially 4 stacks of 1 chip each. Normally you would see something like that where the player uses 10 or 15 chips and drops them into stacks of 5 for easy counting.

In the example given, I would not allow the player to hold the 4 chips in his hand, lay down 3 stacks of 1 chip each, then put the 4th chip back in his stack.

Thanks for all the replies. This certainly reinforces what I was thinking.

There was no time or attempt to gauge others' reactions while he was placing his chips. The action was about as quick as it could be, considering it was laying out the chips individually side-by-side.

No, he never brought out more chips than he was betting. I do see this behavior frequently as well. Bring out a handful of chips, drop a few of them, and return the rest to the stack. I've seen some places cracking down on this.

I know the "accused" player quite well, and am absolutely certain he was not trying to gain an advantage or get away with something. This is just a procedural matter that I want to make sure we get right. My home game is extremely friendly, but we also try to be fairly professional. I'm particularly concerned about situations like this because I don't want my guys to get into any bad habits that could cause them problems if/when they play at a casino.

Papa...
I'm with everyone else...no string bet. Though the most sensible rule is to require an announcement of the action "Call", "Raise 20", "Raise 1,000", etc. That works well in our games. We offer a one time "free" offense to new players, but after that any chips brought forward ARE the bet.