No live roots - repotted too late?

[oldtrlrnr]

Today I repotted two of my Oncidium/Odontoglossum hybrids. Both were apparently healthy plants, judging from their leaves and growing rate. But when I removed them from their plastic pots (had to cut the pots away), both turned out to have tightly wrapped bundles of all-dead roots filling their pots. I cut up their dead roots and removed much of them, leaving some to hopefully help anchor the plants in their new pots, which were ~ 6" diameter, a little larger than the pots they had been in. These new pots were decorative ones with side openings that should provide a lot of aeration. I used an orchid soil mix heavy on bark. On the first orchid, which had a lot of new live roots protruding up into the air, I repotted it whole. I did manage to tuck a few of its live roots down into the new soil.

The other orchid had only a very few live roots, again all above soil level. This one I decided to divide into two plants, each with 3-4 bulbs. I planted each one in pots similar to the first one, using the same soil.

I think that I waited too long to repot these orchids, right? They were probably root-bound already when I bought them about a year ago.

So, aside from repotting sooner, what might I have done better?

Appreciate any advice.

Bob
orchid novice