Only disadvantage I see is summer moisture for the hostas may rot the dormant tulip bulbs.

Sounds good to me! I just planted crocus bulbs and I also have allium bulbs planted with my hostas. I have to admit I don't know if the alliums will rot or not, because they were a 'transplant' earlier this spring, as I had them in a tooooo small bed and had to move them out of necessity. But I feel the same way with the crocus. They will look nice in spring before the hosta's leaf out, and the hostas will cover the foilage later. I also have lily-of-the-valley planted with the hostas. I'm hoping the hostas will cover the LOTV when their leaves start to yellow.
Hostas are pretty tough, and can stand some drier conditions when established, so I don't see any problem with tulip bulbs being planted there.
Besides, I don't know if you planted "perennial" tulips or not, but since most tulips don't come back and bloom the second year, you only need them to survive and bloom in spring then.

They are greigii type, which perennialize well for me.

I'm planting Allium unifolium between my sister's line of Hosta along her driveway. She hasn't watered them in 20 years and they survive on whatever rainwater they get.

She's got sandy soil and NO slugs so she can have all the Hosta she likes...now with bulbs in between for late Spring blooms.

Thanks, all! I planted them today. Kentstar, I have established alliums in my perennial beds, which get watered during the summer. So far they have done just fine.

It's good to hear your alliums do fine among perennials, linnea56.

I've got 50 of the Allium unifolium and just 15 Allium cernuum bulbs. Read I should plant A. cernuum between Lavender since they lean. Luckily I have 4 Lavender Lady plants from last year's sowing that need to be planted out.

I had to tie my hands together NOT to order 50 Allium ostrowskianun (oreophilum)...love that deep pink color. Decided I couldn't stand the dying foliage up front if I used them for border.

Next year, maybe, when I have better feel for building & arranging balanced beds.

My Hostas are grown in a afternoon shaded area, as they don't like full sun here. My tulips are in the full sun with my roses. My tulips are not destined to grow with the Hostas. Al

My preoccupation with doing what was originally suggested is possible damage to hosta roots when planting the bulbs. I have never even seen what hosta roots look like, although I believe hosta roots don't spread much horizontally. Just how close to the stem of a hosta can I punch the planting holes for the tulips?

I have crocus and narcissus with hostas and have for years with no problems.

Lily of the valley has choked out any hostas planted in it though. I love the fragrance but hate the plant for being the worst thug in my garden.

hosta roots don't spread very far. I wouldn't worry about it.